In the wake of a South Carolina stunner, a revamped Republican presidential race moves to a showdown in Florida between Mitt Romney, scrambling to regain his footing, and Newt Gingrich, hoping to take advantage of momentum from his big win.  Presidential candidates Mitt Romney, left, and Newt Gingrich shake hands at the end of Thursday's Republican debate in Charleston, S.C.  Presidential candidates Mitt Romney, left, and Newt Gingrich shake hands at the end of Thursday's Republican debate in Charleston, S.C.  Romney, acknowledging that a controversy about the release of his tax returns had become a damaging distraction, said on Fox News Sunday that he would make public his 2010 returns and an estimate of his 2011 taxes on Tuesday.  Gingrich embraced the nervousness his rise is generating among establishment Republicans who fear his high unfavorable ratings and mercurial personality could spell disaster in November. "The establishment is right to be worried about a Gingrich nomination," the former House speaker said on NBC's Meet the Press, promising to pursue policies that would disrupt their comfort. "We are going to demand real change in Washington."  The four remaining contenders, including Texas Rep. Ron Paul and former Pennsylvania senator Rick Santorum, are slated to meet in Tampa tonight for yet another debate. In South Carolina on Saturday, Gingrich's 40%-28% win over Romney unsettled a contest that just a week earlier seemed all-but-assured to nominate Romney.  For the first time since the modern primary system began, the GOP has a trio of victors from the early contests: Santorum in Iowa, Romney in New Hampshire and Gingrich in South Carolina.  "Usually the game is over by South Carolina," says veteran GOP strategist Ed Rollins. "Today, it's just beginning."  A barrage of TV ads that began weeks ago in Florida is intensifying before the Jan. 31 primary. Romney's campaign and the pro-Romney super PAC called Restore Our Future have bought more than $7 million of airtime, NBC reports. Romney's organization has been urging supporters to cast absentee ballots. Nearly 200,000 Republicans statewide already have voted.  Gingrich "has to get everywhere in a hurry and keep the momentum going in a state that's already been barraged by so many negative ads against him," says Susan MacManus, a political scientist at the University of South Florida in Tampa, site of tonight's debate.  Still, Gingrich was outspent by more than 2-1 by Romney allies in South Carolina to little avail. Surveys of voters as they left polling places showed Gingrich trouncing Romney among conservatives, Tea Party supporters, evangelical Christians — and among those who said the most important candidate quality was electability, a key Romney selling point.  , visit our FAQ's. To report corrections and clarifications, contact Standards Editor  . For publication consideration in the newspaper, send comments to  . Include name, phone number, city and state for verification. To view our corrections, go to  USA TODAY is now using Facebook Comments on our stories and blog posts to provide an enhanced user experience. To post a comment, log into Facebook and then "Add" your comment. To report spam or abuse, click the "X" in the upper right corner of the comment box. To find out more, read the  In 1981, Gingrich introduced a bill to the House floor that sought “to provide for the therapeutic use of marihuana in situations involving life-threatening or sense-threatening illnesses and to provide adequate supplies of marihuana for such use.” September 16, 1981, H.R.4498, 97th Congress, 2D Session  "....are slated to meet in Tampa tonight for yet another debate." Believe that's TOMORROW night.
Romney will release his taxes, Gingrich embraces the nervouness among establishment critics as the GOP race moves to a Florida showdown.