05.15 (00.15) Here are some of the vital Iowa statistics, according to AP.
Median age: 38.1.
Percentage of population 65 and over: 14.9 per cent.
91.3 per cent white, 2.9 per cent black, 5 per cent Hispanic or Latino origin, 1.7 per cent Asian.
Language other than English spoken at home: 6.4 per cent.
High school graduate: 89.6 per cent.
Bachelor's degree or higher: 24.2 per cent.
Median household income: $48,065.
People below poverty level: 11.8 per cent.
Homeownership rate: 72.9 percent.
2008 presidential results: Barack Obama, 54 per cent; John McCain, 44 per cent.
Registered voters: Republican, 613,521, Democratic, 645,475, Undeclared, 717,890.
03.28 (22.28) An article by CBS News has been gaining some traction, with quotes from Rick Santorum apparently saying he doesn't want to "make black people's lives better by giving them somebody else's money." There is also a video in the article of his speech with a woman in the audience nodding and agreeing with him. He appears to stumble over the sentence so it is not immediately verifiable.
At a campaign stop in Sioux City, Iowa on Sunday, Republican presidential hopeful Rick Santorum singled out blacks as being recipients of assistance through federal benefit programs, telling a mostly-white audience he doesn't want to "make black people's lives better by giving them somebody else's money."
Answering a question about foreign influence on the U.S. economy, the former Pennsylvania senator went on to discuss the American entitlement system - which he argued is being used to politically exploit its beneficiaries.
"It just keeps expanding - I was in Indianola a few months ago and I was talking to someone who works in the department of public welfare here, and she told me that the state of Iowa is going to get fined if they don't sign up more people under the Medicaid program," Santorum said. "They're just pushing harder and harder to get more and more of you dependent upon them so they can get your vote. That's what the bottom line is."
He added: "I don't want to make black people's lives better by giving them somebody else's money; I want to give them the opportunity to go out and earn the money."
02.30 (21.30) Herman Cain is back! He has told Piers Morgan that he is "on a mission" to start a national movement to tackle the issues he raised during his campaign. He also says he became a grandfather for the fourth time on New Year's Day, re-emphasising his pledge to always put his family first.
Pressed on which candidate he would endorse, Cain said he would remain unconventional and make his decision later depending on who he thinks will have the best chance of beating Barack Obama.
The media are like rats on a bone. What I do not miss is the pain that all the false accusations have caused my family. I will still be on a mission, because I'm not giving up on all the critical issues during my campaign.
I'm going to go from the campaign to a movement. These issues that I have talked about are not going away. The American people still have a hunger for solutions and that is what I'm going to base my movement around.
Herman Cain during his campaign KAREN BLEIER/AFP/Getty Images
02.18 (21.18) Over on Fox News, Rick Santorum is getting tearful as he talks about the death of his child in 1996 to Sean Hannity. He describes how he brought the dead infant home to meet his other children, saying it was important they knew they had a brother. Santorum has previously been criticised over his handling of his son's death, with liberal Fox News contributor Alan Colmes calling the action "some of the crazy things he he's said and done".
02.03 (21.03) Newt Gingrich is speaking to Piers Morgan on CNN. He says although he may not win in Iowa, he will continue in the caucuses and will build popularity gradually. He also reacts to a Romney attack ad, saying some of the claims are false. He also says he is glad to have run what he calls "a clean positive campaign".
01.41 (20.41) Dana Loesch, CNN political contributor, tells Anderson Cooper that even if Rick Santorum wins in Iowa he simply hasn't got the funds to stretch his campaign further afield. She also remarks that he his campaign has focused on social issues despite the public being more concerned about the economy.
Rick Santorum is a good politician. But he did not win re-election in his own state. He is the wrong candidate for this election. I just do not think he can get that wide appeal after Iowa.
01.15 (20.15) Susan Saulny for the New York Times has compiled a piece about the voters in Iowa, focusing on those who are still undecided. Saulny looks at why so many are finding it difficult to commit to one candidate.
In the summer days leading up to the Ames Straw Poll, that early, informal contest for presidential contenders, Jason Anderson was “totally pumped up,” as he put it, for Tim Pawlenty, a former governor of Minnesota who seemed to be a promising candidate for the Republican nomination.
“He gave me such a good feeling that six or seven of my buddies, all Tim fans, we drove out to the poll to root for him,” said Mr Anderson, 35, right, a father of two from Ankeny, a small town north of Des Moines. “It was like a rock concert, we were so excited.”
Mr Anderson’s emotions were different the next day, when Mr Pawlenty, finishing in a disappointing third place, dropped out of the race.
“I felt it in a big way,” Mr Anderson said.
His mood brightened again only when Herman Cain’s candidacy took off two months later. In Mr Cain’s business-minded philosophies, Mr. Anderson, who works in the auto insurance industry, thought he had found another good match. But when Mr Cain suspended his campaign in the face of escalating accusations of sexual misconduct in early December, Mr Anderson felt that sinking feeling again. Frustration ensued.
In an interview in mid-December, Mr. Anderson vented: “I hate wavering back and forth. It’s been like a rollercoaster.”
00.35 (19.35) Is Rupert Murdoch a Santorum fan? The owner of Fox news, and occasional pie target, is using his brand new Twitter account to produce a stream of nice things about the GOP hopeful. Here's the latest:
00.15 (19.15) Our own Alex Spillius is measuring Santorum's rise by the calibre of his media coverage:
There is a crush waiting for rising star Rick Santorum to speak at Pizza Ranch, Altoona. The A List media presence reflects his late frontrunner status and includes the following: Joe Klein (Time), Howard Fineman (Daily Beast), Charlie Hurd (New York Post), Perry Bacon (Washington Post). And not forgetting not one but two representatives of the Telegraph Media Group. A week ago Santorum would have struggled to get a Des Moines Register reporter along.
The celebrity warm up for Rick Santorum is introduced as Brad Thor, a New York Times best selling author. He is one of Santorum's and a 'great conservative'. Is he Santorum's answer to Chuck Norris, Mike Huckabee's celeb backer in 2008?
23.22 (17.22) Rev Franklin Graham, the son of televangelist Billy Graham, has just been on CNN, where he was asked whether Evangelicals could support Mitt Romney, despite his Mormonism.
I have big differences between the Mormon faith and what I belive but we're not voting for a pastor-in-chief, we're voting for a commander-in-chief. We should vote for the person best qualified to lead this country.
He declines to publicly back anyone but says he's met all the candidates except for Ron Paul and think they could all be good presidents.
23.05 (17.05) If you haven't seen it yet, Pets with Newt is essential reading. Find out why Flint, Midnight, Maggie and Twinx are all backing the former Speaker (sadly, none of them can vote in Iowa.
22.45 (16.45) In Des Moines, Philip Sherwell, the Sunday Telegraph's US Editor, has been keeping an eye on the Democrats.
The focus today is of course on the Republican candidates frantically criss-crossing Iowa in a last-ditch quest for votes, but the Democrats are also in town. The Democratic National Committee has set up office in a central Des Moines hotel where they are seeking to counter the Obama-bashing message of the GOP candidates.
When I swung by the “war room” today, even the promise of free coffee and muffins was not proving much of a lure - just a handful of reporters were present for a press briefing
But significantly, even before the first votes are cast, the Dems here are training their fire on Mitt Romney and his record at Bain Capital, the private equity company where he earned his $200 million-plus fortune. They are highlighting the jobs lost at some companies in which Bain invested – a message that they hope will resonate strongly with working-class voters in the rust-belt swing states that could decide the general election.
Romney of course showcases his private sector credentials at every campaign appearance. He acknowledges that some Bain investments failed, but says that overall 100,000 jobs were created by Bain while he was at the helm.
I wrote in December about how Team Obama is preparing to hammer Romney on Bain.
Ron Brownstein, the editorial director of National Journal and a veteran political commentator here, told me at a Romney meet-and-greet this week that he believes that how the electorate views Romney’s record at Bain will determine the next election during these tough economic times. Job creator or asset-stripper? A crucial matter of perception.
A meagre turnout at the Democrat war room.
22.30 (16.30) Ron Paul's campaign has just announced they have 1,480 precinct captains who will speak on their behalf in tomorrow's caucuses. That's a pretty impressive amount given that there are 900 caucus locations. Romney's campaign has been keeping its number secret (possibly because it's very high and they want to release it to maximum impact tomorrow morning). Perry's camp claims to have 1,500 while Gingrich has around 1,000.
22.15 (16.15) While candidates spend their Iowa days pressing the flesh and meeting the folks their evenings are consumed by cable news appearances. Tonight's schedule* (courtesy of Politico) shows Gingrich taking up the most air time. Neither Romney nor Paul have any scheduled appearances.
• Newt Gingrich is scheduled to be on CBS's "Evening News" at 6:30 pm
• Michele Bachmann is scheduled to be on CNN's "Erin Burnett OutFront" at 7 pm
• Bachmann, Gingrich and Rick Santorum are scheduled to be on Fox News's "Hannity" at 9 pm
• Gingrich is also scheduled to be on CNN's "Piers Morgan Tonight" at 9 pm
• Rick Perry is scheduled to be on Fox News's "On The Record with Greta Van Susteren" at 10 pm
*All times are Eastern Standard ie five hours behind the UK and one hour ahead of Iowa.
22.10 (16.10) For Gingrich and other candidates trailing in the polls there is still one glimmer of good news: around 40 per cent of likely caucus goers say they could still change their minds on who to support. That same figure will also be a worry for Romney. If those undecided voters were to swing behind Santorum, the former Massachusetts governor could see 2008 history repeating itself as he once again loses Iowa to an a social conservative.
21.40 (15.40) The LA Times's James Oliphant tweets from a bleak-sounding Bachmann campaign stop:
21.30 (15.30) If you haven't seen it yet have a look at Alex Spillius's analysis of Mitt Romney's campaign.
Where his rivals have been unpredictable, error-prone and disorganised, Mr Romney has been steady, virtually fault-free and well drilled. He has retained a campaign structure from his failed bid for the nomination in 2008 and has raised much more money than anyone else partly through his Wall Street connections.
His great problem is personality. As one US commentator put it, there is a “dazzle gap” with Mr Romney, a polite way of saying he is rather dull. Even supporters rarely summon a superlative to describe their reasons for backing him. “Solid” and “professional” are words used often.
The more conservative among the party faithful regard him as ideologically dubious, a northeastern liberal sham who will say anything to get elected. Christians are suspicious of his Mormonism, though they are usually too polite to say so.
20.30 (14.30) Jon Swaine has been criss-crossing Iowa on the trail of several candidates today:
Michele Bachmann, who is predicted by polls to finish last out of the candidates competing here (ie. excluding Jon Huntsman), has just given a defiant speech following a campaign stop on Elm Street, West Des Moines.
Comparing herself as usual to Ronald Reagan and Margaret Thatcher, she said that not only would she win the Republican nomination, she would also beat Barack Obama to become president. "I will be America's Iron Lady," she said.
She tried to quash rumours that she may pull out of the race altogether if she does finish last. "We've already booked our tickets to South Carolina," she said, adding later: "We will be in New Hampshire".
She also struck an even more alarmist tone than usual over the latest developments in the Iranian nuclear programme, saying: "Iran is on the verge of a nuclear weapon and will use it against Israel and the United States". In a dig at Ron Paul, who urges restraint in the crisis, she said she was not prepared to wait for a US city to be levelled by an Iranian nuke before taking action against Tehran.
Bachmann has been making the Thatcher comparison for a while now. Some say they can see the similarities although Mrs T is unlikely to say that the Falklands War began in 1992..
20.15 (14.15) Speaking of previous winners, a lot of people have been comparing Santorum's rising poll numbers to Mike Huckabee's victory in 2008. There are definitely similarities: both men are staunch religious conservatives who put abortion and God at the centre of their campaigns and whose numbers climbed in the final days of the race. But does it necessarily follow that Santorum is now on course to victory?
The answer is probably not. In 2008, Huckabee overtook Romney in the polls in the beginning of December and stayed in front pretty much right up until polling day on January 3. Santorum's surge is both later and smaller. He's still in third place and his rise has come in the very last days of the campaign - meaning there's limited time for him to capitalise on an upturn in donations and volunteers.
20.00 (14.00) A quick reminder that while Iowa does a good job of winnowing out the field, its record of picking an evenual winner is very mixed:
19.45 (13.45) Iowan television has been saturated with political advertising in recent weeks, sometimes as many as 12 ads in half an hour. Perry is leading the charge, spending about $4.5 million on TV ads. Here's a soaring example of what his money bought:
If you're interested in the ad war, then have a look at this graphic from the New York Times.
19.30 (13.30) Ron Paul's national campaign chairman, Jesse Benton, is on television declaring a two-horse race between "Mitt Romney, the establishment status-quo candidate and Ron Paul, the candidate of the people". Is Dr Paul, 76, too old to be president?
You've got to look at the man. He's the fittest man I've ever been around - he walks three miles a day and bikes 15 miles. He's young and sharp.
Paul would be 77 at the time of the inauguration, making him eight years older than Reagan was when he was sworn in for his first term at the age of 69.
19.00 (13.00) Alex Spillius files some notes from Des Moines:
The buzz here is that Rick Santorum could pull off a surprise win. Christian conservatives are coalescing behind him as the anyone-but-Romney candidate, which is very bad news for Michele Bachmann and Rick Perry.
The rate at which he has gained support in the past week has been spectacular and unprecedented as far as anyone can recall. In 2008 Mike Huckabee surged to the front late on, but by the time of the final Des Moines Register poll a few days before he was in front.
Santorum was third in that, a full nine points behind Romney, but the feeling on the ground is that his surge has continued since the results were released on Saturday.
Just bumped into David Yepsen, the former Des Moines Register columnist and guru on all things political in Iowa, and he points out that even finishing second for Santorum will set him up for the next few races and begin the whispers about the vice-presidential nod.
18.45 (12.45) One of the many, many clichés of US presidential politics is that there are three tickets out of Iowa i.e. only the top three from the caucuses have a hope of going foward in the primary.
That probably won't be the case this year for a couple of reasons. Let's imagine tomorrow night goes Romney, Paul then Santorum (as the polls are indicating). It would probably be the end of Bachmann, whose funds are low and who has limited appeal outside of very religious circles.
But Gingrich and Perry will almost certainly stick it out. Despite an awful 10 days in Iowa, Gingrich is still leading the polls nationally and has good numbers in Florida and South Carolina, the next states after New Hampshire. He also will be looking foward to the debates beginning January 7, where he normally puts in a strong performance.
Perry, meanwhile, has an enormous war chest to keep him going and may fair better in a southern state like South Carolina than he's currently managing in either Iowa or New Hampshire.
18.35 (12.37) Romney is onstage in Dubuque where much of his pitch is focused on Obama rather than any of his Republican rivals. He repeats a good line from earlier, quoting the president as saying that if he doesn't fix the economy then he's looking at a one-term administration. "I'm here to collect!" Romney cries. In recent weeks he's also tried to expand his image beyond just economic pragmatism.
This isn't just an election about policy or procedures or dollars or cents. It's an election about the soul of America. This country of ours was founded on an extraordinary set of principles.
18.20 (12.20) The New York Times' polling guru, Nate Silver, speculates on the fate of two former frontrunners:
18.05 (12.05) A quick word about a candidate who's not on Iowa ballot but is pouring money and operatives into the state: Barack Obama. Tomorrow night, as the rest of the country is watching the GOP results, the president will be using Skype to speak to the Democrat activists who propelled him to victory in 2008. The next day he will be in nearby Ohio, a key swing state, where he'll speak about the economy.
There are lot pitfalls facing an incumbent presiding over a struggling economy but if you're interested in his re-election plan then have a look at this nakedly political video by Jim Messina, the Obama 2012 campaign manager (and excuse the bizarre moment of swearing):
17.50 (11.50) The American broadcast media has a fascinating relationship with Ron Paul. The major news channels acknowledge that he's a serious candidate and faithfully report his growning popularity but they simply cannot stay interested in what he's saying.
CNN was just covering one of his rallies in Des Moines but as soon as he began in his familiar riff about personal liberty they cut away. As he predicted, Paul got big cheers when he said that 70 per cent of Americans support ending the war in Afghanistan and bringing the troops home.
17.38 (11.38) There will be a flurry of polls over the next 24 hours but here's the most recent from Insider Advantage, which surveyed 729 likely voters yesterday.
It shows Romney and Paul in a statistical dead heat but with Santorum closing in behind. Interestingly, the poll also finds that Paul has a huge advantage amon independents, a traditional Romney strong point. Around 38 per cent of the Indies went to Paul, compared to only 18 per cent for Romney.
17.25 (11.25) Our own Alex Spillius has written this useful guide explaining how the caucus system works.
In Iowa tomorrow, voters will arrive at 7pm at 1,774 locations across the state including schools, libraries, hotel meeting rooms and even people’s homes to cast their vote for the Republican presidential candidate. The numbers at any location will vary between a handful and several dozen.
A caucus is a small political meeting, which begins with someone being chosen to chair proceedings. Local supporters of candidates then argue their case for a few minutes before votes are cast. A north American peculiarity, the provenance of the word is disputed.
Unlike primary and general elections, where larger polling stations are open all day, the meetings last about an hour. Votes are then counted on the spot and are phoned in to county officials.
Voters write their choice on a bit of paper or tick a name on a more conventional-looking printed sheet and drop it in a box — sometimes a shoebox or cardboard box. Voters are not limited to choosing official candidates. One Republican official said: “You could vote for your granny if you wanted to.” Anyone can vote in the Iowa Republican caucus, as long as they are an adult resident in the state and have valid identification.
17.16 (11.16) Ron Paul is on CNN with his son, Senator Rand Paul. The generations of Pauls have just landed a one-two punch on Santorum, with the older man describing him as "very liberal".
Look at his record. He's spending too much money. He wasn't leading the charge to slash the budget or roll back big government.
Paul Snr is in his trademark ill-fitting suit while his son wears a more casual cardigan. Both staunchly defend their campaign's foreign policy positions of non-intervention and withdrawing American forces around the world. "When I talk about the war you will hear the loudest cheers," he says.
17.10 (11.10) There is absolutely nowhere to hide in the Hawkeye State if you're trying to escape from a handshaking presidential wannabe. Have a look at the Politico daily calendar to get a sense of the pace of campaigning going on. Most candidates have at least five events today.
17.05 (11.05) Jon Swaine tweets this picture of Santorum leaving the Reising Sun coffee shop in Polk. The candidates says "We're seeing momentum and intensity" as he predicts a top-three finish.
16.55 (10.55) As the day begins to warm up politically in Iowa (temperatures are still below freezing) let's take a quick review of the candidates and where they stand:
Mitt Romney, former Massachusetts governor, 23 per cent.
The race's slow-but-steady frontrunner is looking confident with just under 36 hours to go until polls open in Iowa. A win here followed by a crushing victory in New Hampshire could give Romney an unassailable lead.
Ron Paul, Texas congressman, 22 per cent
The Libertarian has had a rough two weeks following the emergence of racist newsletters that he published in the 1980s and 1990s but his core support is holding strong and he's statistically tied with Romney. If the weather is bad tomorrow his devoted loyalists could storm to victory.
Rick Santorum, former Pennsylvania Senator, 16 per cent
Santorum has been ignored for most of the campaign but today is threatening an astonishing upset in Iowa. He is successfully rallying both Evangelicals and conservatives and may finally by the anti-Romney so many in the GOP are waiting for.
Newt Gingrich, former speaker of the House, 14 per cent.
Has been hit by waves and waves of negative advertising that have dragged his poll numbers from the low 30s to the low teens in just a month. Gingrich has admitted he isn't going to win but has vowed to stay the course in the hope of redemption in South Carolina and Florida.
Rick Perry, governor of Texas, 12 per cent
Perry's camp is watching in despair as Rick Santorum gathers up the Evangelical vote. The former Air Force pilot is the biggest spender on TV air time in the tiny state but is struggling to avoid to stay out of the bottom three.
Michele Bachmann, Minnesota congresswoman, 7 per cent
Bachmann was born in Iowa, is a ferocious conservative and over the summer enjoyed a strong lead for several weeks. Now she is looking down the barrel of a last-place finish which would probably end her candidacy.
Jon Huntsman, former governor of Utah, 2 per cent
The former ambassador to China is not competing in Iowa and is placing all his hopes in New Hampshire. Expect him to finish dead last tomorrow.
16.32 (10.32) Gingrich has just admitted that he's not going to win the caucuses tomorrow
I don't think I'm going to win. Those negative negative ads have done enough damage.
He repeatedly cites the $3.5m of negative ads aimed at him but says that the people of Iowa are beginning to see through them and reminds reporters that around 40 per cent of caucus goers say they could still change their minds.
16.23 (10.23 in Iowa) In a freezing Polk City Rick Santorum has been fielding questions on everything from bipartisanship to Syria to the environment. On that last topic he rails against the Obama administration's green regulations, which he says are the result of a hatred of carbon and blue collar workers. One of the most interesting moments is when he's asked if he has the funding and the organisation to defeat Obama's lethal re-election campaign. "We've raised more in the last few weeks than we have in the last few months, he says. Our own Jon Swaine has been talking to some of the people at the event.
Jim-Bob Duggar , a televangelist from northwest Arkansas, has driven through the night with 12 of his 19 children, his mother and his sister, to be here backing Mr Santorum. "We are calling on Christian conservatives around the country to come together and send Rick to the White House," he told The Daily Telegraph. Right-wingers need to be aware that Mitt Romney made it easier for teenage girls to obtain abortions as Governor of Massachusetts, he said.
15.42 A last minute blitz of campaigning is expected today, before Iowans cast the first votes of what will be a year-long fight to the November 2012 elections. Mitt Romney has made little secret that he hopes a first- or second-place showing in Iowa, followed by a win in New Hampshire one week later, and another in South Carolina after that, will let him win the nomination relatively early and focus his energies on taking on Barack Obama for the White House.
15.11 A Telegraph video of Mitt Romney saying he is "encouraged" by Iowa support:
14.45 Several candidate have surged up the Republican field and then dropped back down, notably Michele Bachmann, Rick Perry and Herman Cain. Newt Gingrich is the latest to apparently run out of puff, to be displaced by the ultra-Right-wing former Pennsylvania Senator Rick Santorum, who, until last week, was relatively unknown. Here, Jon Swaine looks at his late run up the ranks:
Mr Santorum, who has spent three months travelling the state in a pickup truck and without any staff, has become the latest alternative to Mitt Romney to rise sharply in the opinion polls.
Having been stuck in low single-digits throughout the campaign, he came third behind Mr Romney and Ron Paul in the final Des Moines Register poll, backed by 15 per cent of likely caucus-goers.
However the 53-year-old, who is supported by many evangelical Christians for his zero-tolerance stance on abortion, overtook Dr Paul when the last two days of the four-day survey was considered separately.
Republican presidential candidate Rick Santorum campaigns at the Smokey Row Coffeehouse in Oskaloosa, Iowa
14.32 From Bill Clinton to John Boehner, American politicians are known for welling up. Here is a Telegraph video of Newt Gingrich brought to tears talking about his late mother, while Mitt Romney compares President Obama's comments on the economy to Marie Antoinette's famous "let them eat cake" remark:
Gingrich was speaking to a bipartisan group of 100 Iowa mothers as he recalled childhood memories of his mother Kit Gingrich, who died in 2003 at the age of 77.
"I get teary eyed every time we sing Christmas carols. Excuse me. My mother sang in a choir and loved singing in a choir. And I don't know if I should admit this, when I was very young, she made me sing in the choir," Gingrich said.
14.24 Frontrunner Mitt Romney tweeted last night:
14.19 An even number of voters want a candidate who shares their values as want a candidate who can beat Barack Obama, according to an NBC/Marist poll. Matt Strawn, Iowa Republican Chairman, said:
The first thing you see when you talk to any Iowa Republican is that desire to beat Barack Obama.
14.10 Newt Gingrich, who recently enjoyed a surge in the polls but who has faded just as fast, has been trying to recapture voters late in the day. In an interview with Reuters, he attacked Romney, while attempting to emphasise that he doesn't criticise his rivals as part of his "positive" campaign:
By the time we get to South Carolina, it will be very clear the gap between a Massachusetts moderate who hides his record behind negative ads and a conservative who's talking about positive ideas.
As major donors in this country realise how much Mitt Romney's not going to defend them and not going to protect them and not going to help them, that he will face a lot bigger challenge than I will.
13.02 Speaking on Monday night, Mitt Romney made an eleventh-hour pitch to Iowa voters:
I can't tell you who's going to win this thing. But I do believe that I'm going to have a great deal of support and that that will give me the kind of boost I need as I go into a season of (contests in) a number of other states. This is a process that begins here.
12.23 Jon Swaine's story from this morning's Telegraph on how Mitt Romney could pull off a historic double victory in Iowa and New Hampshire:
The former Massachusetts governor leads the party field both in Iowa, where tomorrow’s caucuses will give the candidates their first test, and in New Hampshire, where voters go to the polls next Tuesday.
If successful, Mr Romney would become the first Republican challenger in the modern primary system’s 35-year history to win both states. Party strategists concede that such a scenario would effectively end the contest after just one week of voting.
12.00 (0600 CST) Good afternoon - or morning to our US readers - and welcome to our live rolling coverage of the 2012 Iowa Republican primary.
So far the Republican elections have already been tumultuous with rumoured sex scandals, embarrassing gaffes and cries of racism, witchcraft and cronyism, and the polls haven't even opened. Now, with 24 hours to go before the first caucuses open in Iowa on Tuesday, Americans will finally have their chance to give their verdict on the Republican candidates still in the running to face Barack Obama in the 2012 presidential election.
Mitt Romney, the former Massachusetts governor, is perhaps the favourite in the race having consistently faired well in the GOP debates in the run up to the polls. He is now on course for a historic double victory.
Rick Perry, the Texas governor, was an early favourite but fell down after one of the most excruciating 53-seconds in a televised debate since John F Kennedy clashed with Richard Nixon in 1960. Here is that "oops" moment again for those who may have missed it the first time.
Herman Cain, of Godfather's pizza fame, grasped the lead from Perry following the gaffe, only to fall down himself after a string of allegations about lurid affairs with several women. Despite enjoying a significant lead in the straw-polls, Cain dramatically suspended his campaign.
Newt Gingrich, the former House Speaker, was given a surprise boost in the Republican race after Herman Cain pulled out but was weakened by claims that he was paid up to $1.8 million (£1.14 million) for advising Freddie Mac at the height of the financial crisis. He was also hit by allegations that he divorced two of his wives while they were suffering from cancer and multiple scerosis respectively.
The candidates still in the race include:
Mitt Romney, former governor of Massachusetts
Ron Paul, US representative for Texas's 14th district
Michele Bachmann, US representative for Minnesota's 6th district
Jon Huntsman, former governor of Utah and US ambassador to China
Rick Santorum, former US senator for Pennsylvania
Rick Perry, governor of Texas
Newt Gingrich, former Speaker of the House
Those who have withdrawn include:
Herman Cain, businessman
Tim Pawlenty, former governor of Minnesota
Gary Johnson, former governor of New Mexico
Here is our team covering the US elections: