Updated. 11:26 a.m. ET
NORTH CHARLESTON, S.C. -- A week ago, Mitt Romney was considered all but a shoo-in to win the South Carolina Republican presidential primary. Coming off of perceived victories in the Iowa caucuses and New Hampshire primary, he was strongly favored in the polls -- one of which showed him leading his competitors handily, by more than 20 points.
A lot can change in a week.
Today, as Palmetto state voters head to the polls, only four men remain in the race for the Republican presidential nomination -- and Newt Gingrich appears to be the at the head of the pack.
After an epic flameout in the Iowa caucuses, many thought Gingrich was all but done for in the presidential race. But the former House speaker has been steadilyon the campaign trail in South Carolina, in part due to strong, confident performances in back-to-back debates.
On Friday, a new poll out of Clemson University poll showed. The poll has 4.73 percent margin of error.
Romney on Friday sought to downplay expectations for his performance in today's nominating contest, telling reporters he was "cautiously optimistic" about its outcome but that "we'll see what the numbers are in the final tally."
"I sure would like to win South Carolina, but I know that if those polls were right, regardless of who gets the final number, we're both going to get a lot of delegates," he added.
"He just had a bad week," said Chip Felkel, an unaligned South Carolina Republican strategist. "All the sudden inevitability is gone."
It was a tumultuous week for politics in general down in the Palmetto state: On Thursday, Iowa Republican Party officials belatedly announced that Rick Santorum, not Romney, actually earned the most votes in the state's January 3 caucuses. While they did not declare a winner on Thursday due to incomplete results at some precincts, Iowa GOP officials did formally say Santorum won on Friday night.
Also on Thursday, Texas Governor Rick Perry withdrew from the race, throwing his support to Gingrich on the way out. The same day, ABC News aired an interview in which one of the speaker's ex-wives claimed Gingrich had asked if she'd consent to an "open marriage" with him -- allegations the candidate has vociferously denied. Romney, meanwhile, has faced incessant questions about issues related to his personal wealth and the release of his tax returns.
In Thursday night's debate, he was particularly criticized for announcing that he would not be announcing his tax returns until April -- at which point the nominating contest could be wrapped up.
Romney's supporters quickly attempted to minimize the issue, rushing to his defense and pointing out that several of the candidate's competitors have not committed to releasing their tax returns at all. (In the debate, Santorum said he didn't have access to his tax returns because they were at home on the computer; Ron Paul cited the embarrassment of putting his financial information "up against" that of his competitors.)
"I don't see what all the fuss is about," said former Minnesota Governor Tim Pawlenty, defending Romney after the debate.
"What he said tonight, and what he's said consistently, is he is going to release his tax returns, it's going to be April or sooner, and he's going to do it for multiple years. And that's more than any other candidate on the stage said," Pawlenty said.
"The primary could be going on to June, or go into August," Romney adviser Stuart Stevens pointed out.
Felkel, the GOP strategist, cited Romney's general "discomfort" talking about his personal wealth -- not his actual positions surrounding it -- as the candidate's real problem.
"He just has a tremendous level of discomfort talking about his finances," Felkel said. "I can't believe an economy guy couldn't answer some of these questions. Eight years of running for president, you should have an answer for questions about your wealth and your taxes, and he didn't have an answer for that. He didn't have a comfort level there."
The candidate's campaign has not refrained entirely from attacking Gingrich -- on Friday, Romney called on the candidate to release the full documentation of his 1990s-era ethics investigation, and his campaign held a conference call blasting Gingrich as the "granddaddy of earmarks" -- but at a Friday rally, the candidate seemed determined to stay focused on President Obama. Unveiling the endorsement of Virginia Governor Bob McDonnell, Romney lashed out at the president, not Gingrich.
But even some of his supporters were worried about the former Massachusetts governor's prospects in South Carolina.
Sandra Winter, a Romney fan from Summerville, S.C., said Gingrich's recent rise was "a concern to me."
"I think he's had two great debates; he's an excellent debater, and I think that people are taken over by the way he projects himself," Winter said. "It's gonna be really close. If Romney does manage to succeed, it'll be very close. It's a tight race."