Updated

A two-man fight for Florida is emerging ahead of the state's final Republican presidential debate Thursday, with polls showing the race neck and neck as Mitt Romney and Newt Gingrich pound each other over personal and professional vulnerabilities.

A new Rasmussen poll out Thursday has Romney retaking the lead with 39 percent over 31 percent for Gingrich. Rick Santorum had 12 percent and Ron Paul was taking 9 percent of the vote among the 750 likely GOP voters polled.

A Time magazine/CNN poll out Wednesday had the race in a virtual tie between Romney and Gingrich, 36-34 percent among 369 registered Republicans who are likely to vote in the Florida presidential primary. The survey was taken between Jan. 22-24. Rick Santorum had 11 percent and Ron Paul was taking 9 percent of the vote.

The latter two candidates are far back in Florida, in part because they have been concentrating on other states.

According to the latest American Research Group poll of 600 likely GOP primary voters, Romney leads his rivals with 41 percent followed by Gingrich with 34 percent, Santorum with 9 percent and Paul with 7 percent.

With the race tight, Romney's campaign may be benefiting from a decision to concentrate on early voting. The ARG poll found 17 percent of likely primary voters said they had already voted absentee or early. Among this group, Romney was leading Gingrich 51-39 percent. For those who haven't voted yet, the race was 39-33 percent Romney to Gingrich.

The Florida Republican Party told Fox News that as of Thursday morning, 501,316 absentees ballots had been requested and 254,485 had been returned. Florida, which allows early voting, has also had 151,678 early votes in the polls so far. Early voting ends Saturday.

A new poll on Thursday shows the former Massachusetts governor is also in a better place to challenge President Obama. According to a Quinnipiac University poll of Florida voters on Thursday, Romney runs even with Obama 45 - 45 percent in Florida while Gingrich is 11 points back from the president, 50 - 39 percent.

In the poll of 1,518 registered voters in Florida, independents support Romney against Obama almost evenly, but they break for Obama over Gingrich by a substantial 50-33 margin.

Santorum trails Obama 49-40 percent while Paul trails the president 47-39 percent.

The winner of Tuesday's primary will score something no one has yet claimed in a tumultuous primary season: a second victory. The first three nominating contest have gone to three different candidates; only Paul has not topped a primary or caucus vote but he has been accumulating delegates for what he calls his "cause."

Sharp exchanges Wednesday highlighted the stakes in the battle to determine Obama's challenger. Gingrich tried to paint Romney as out-of-touch by noting his Swiss bank account and another in the Cayman Islands.

Romney, a businessman-turned-politician, couldn't escape questions about his wealth from others. At a forum at the Spanish-language Univision Network, Romney was asked point-blank how much money he had.

"Well, it's -- it's between a $150 and about $200 and some odd million," he responded after trying to turn the question back on the forum's moderator. "I think that's what the estimates are, and -- and, by the way, I didn't inherit that."

Gingrich faced uncomfortable questions of his own during his turn at Univision. He dismissed suggestions that he lacked standing in the mid-1990s to criticize President Bill Clinton's infidelity when he was carrying on an affair of his own, arguing that Clinton had lied under oath and that was the real issue in the impeachment of the president.

Meanwhile, elected officials backing Romney, including 2008 GOP nominee John McCain, sought to keep the focus on Gingrich's turbulent time in Congress and lucrative consulting work after he left. Gingrich, whose crowds consistently reached into the thousands, cast the stepped-up critiques as a sign of his momentum.

"What you have right now is the entire establishment in panic mode running around saying whatever comes into their mind next," Gingrich told reporters.

The hits for both Romney and Gingrich were coming from many directions.

The "super" political action committees backing the two leading GOP candidates have spent more than $10 million combined on ads so far in Florida, far more than their respective campaigns. The Romney-leaning Restore Our Future has spent $8.8 million in ads as of late Tuesday, bringing the total of ads supporting Romney in the state to $14 million, not counting the cash already spent on radio and Internet advertising.

As of late Tuesday, the Gingrich-backing Winning Our Future had booked $1.8 million in television ads in Florida, a check made possible by a new donation from Miriam Adelson. She and her husband, Sheldon, this month gave $5 million apiece to the group, which supports Gingrich but legally must remain independent.

Obama was amid a campaign-style swing of his own, pressing a populist theme of tax fairness. Republicans said Obama's call was little more than code for tax increases and charged those would hinder the economic recovery.

Back in Florida, Santorum was recognizing that he stood almost no chance to win the primary and wasn't planning spending money on ads though he was actively engaged on the ground courting voters and pastors who can rally Christian conservative voters.

His campaign, however, is emphasizing raising money and calling potential supporters in upcoming primary states.  Chuck Laudner, an influential adviser who helped Santorum score an upset victory in the Iowa caucuses, was headed back to the Midwest to start piecing together coalitions in Missouri and Minnesota.

Paul has been virtually absent from Florida except for appearances built around the two debates. He was concentrating instead on caucus states where his loyal backers can carry a louder voice.

The Associated Press contributed to this report.