The Republican presidential candidates have entered the final frenzy of campaigning before Tuesday's Iowa caucuses, the first major contest in the fight for the party's nomination to take on Barack Obama for the White House.
In a race that remains too close to call, a poll published over the weekend showed former Massachusetts governor Mitt Romney, Texas congressman Ron Paul and former Pennsylvania senator Rick Santorum all in contention for first place.
The voters will finally have their say after months of polls and debates, with well over 100,000 Republicans expected to turn out to vote in Tuesday's caucuses, the first in a series of contests that could go all the way to the summer. The winner will take on Obama in the general election on 6 November.
Santorum, the most hardline conservative of the pack, has adopted the toughest approach of all the candidates towards Iran. Speaking on NBC, he accused Obama of being too weak, and said that if he was elected as president he would order the Iranians to open their nuclear facilities or face a US attack. Short of cash and staff, Santorum has waged a low-cost campaign, driving round Iowa over the past year for a series of town hall meetings. His approach appears to be paying off, with a surge that has seen him jump to contention from single-digit figures.
The campaign overall has been dominated in the past week by one of the most expensive and relentless advertising blitzes Iowa has ever experienced, much of it directed by Romney against Newt Gingrich, who has since plummeted in the polls.
Gingrich, out on the campaign trail , in a desperate bid to stop his poll slump, finally hit back at Romney. Barely able to conceal his frustration over the volume of negative ads, he said: "Romney would buy the election if he could."
At a later campaign stop he accused Romney of spending $3.5m (£2.25m) to lie about him. "If you are willing to be dishonest to get to be president why would we think you will be honest once you are president."
In this topsy-turvy campaign that has seen candidates rise and fall on a regular basis, Michele Bachmann, winner of the Iowa straw poll in August, an early indicator of popularity, looks headed for last place. Bachmann, who lost two key staff last week and has attracted only sparse crowds, said on Sunday she was looking for "a miracle".
A Des Moines Register poll published on Saturday, regarded by campaign teams as reliable, had Romney on top with 24%, Paul at 22%, Santorum at 15%, Gingrich at 12%, Rick Perry at 11% and Bachmann at 7%. The other candidate, Jon Huntsman, opted against fighting in Iowa and is waiting in New Hampshire, where a primary is to be held on 10 January 10. The Republican governor of Iowa, Terry Branstad, who appeared on Sunday's the Sunday morning talk shows, described the contest as "wide open", and warned against dismissing Texas governor Rick Perry.