Not 24 hours after Mr. Gingrich’s victory in the South Carolina primary, the two camps were trading charges over the Congressional ethics inquiry on Mr. Gingrich in the 1990s, over Mr. Romney’s tax returns and over whether Mr. Gingrich’s consulting work for the government-sponsored mortgage lender Freddie Mac amounted to lobbying.
Their immediate battleground is Florida, which will hold its primary in eight days. But their intensifying duel was also shaping up as a proxy battle in the fight between the Republican Party’s establishment wing — in favor of Mr. Romney — and a grass-roots insurgency that, for now at least, seems to be coalescing around Mr. Gingrich as a no-holds-barred opponent to President Obama in the fall.
“He’s done something that most people don’t really understand,” said Mallory Factor, a Republican activist based in South Carolina who organizes a weekly meeting of conservative donors in New York City. “He has channeled the frustration of the Republican base and independents.”
Mr. Gingrich moved quickly to take advantage of his victory with a new fund-raising push that he told supporters in a Twitter message had already brought in more than $1 million by late afternoon Sunday.
But perhaps the biggest question hanging over Mr. Gingrich’s ability to prevail in Florida is whether Sheldon Adelson, the billionaire casino owner who bankrolled the “super PAC” Winning Our Future that ran negative ads against Mr. Romney in South Carolina, will write another multimillion-dollar check to finance similar attacks in Florida, where airtime is expensive.
Mr. Romney’s decision to release his tax returns on Tuesday — after weeks in which he had equivocated about whether and when he would release them — reflected the loss of what had seemed to be his commanding front-runner’s position. After saying just days ago that he would release them in April, Mr. Romney said on “Fox News Sunday” that on Tuesday he would make public his return from 2010 and an estimate of the numbers in his 2011 return.
Moving to strip Mr. Gingrich of his anti-establishment credentials, Mr. Romney and his campaign on Sunday began a more assertive effort to define Mr. Gingrich as a Washington insider whose tenure as House speaker was marked by chaos and ethical lapses.
They pressed for more information about the ethics investigation into Mr. Gingrich and portrayed him as part of a special interest culture. Speaking of Mr. Gingrich at an outdoor rally in Ormond Beach, Fla., Mr. Romney said, “He’s been working as a lobbyist, selling influence around Washington.” He also called him a “failed leader.”
Mr. Gingrich dismissed the claim that he had been a lobbyist. But he belittled Mr. Romney as inauthentic and vulnerable because of shifts away from more liberal positions he once held.
“Governor Romney’s core problem was that as the governor of Massachusetts, he was moderate, which by the standards of Republican primary voters is a liberal. And he can’t relax and be candid,” Mr. Gingrich said on “Face the Nation.” “He’s been dancing on eggs trying to figure out how to find a version of Romney that will work.”
As the campaigns made their way to Florida on Sunday, they were looking at a reset landscape where Mr. Gingrich has momentum but Mr. Romney has important financial and organizational advantages.
Mr. Romney and the super PAC supporting him, Restore Our Future, have run millions of dollars in advertisements in Florida for weeks, while Mr. Gingrich and Winning Our Future have run none.
Rick Tyler, a senior adviser to Winning Our Future, said the group was seeking to spend $10 million in Florida; when asked if it had raised enough to meet that goal, Mr. Tyler said, “Not yet.”
It was unclear whether Mr. Adelson would send millions of dollars more to the group.
After Mr. Gingrich came in fourth in Iowa, where he was pummeled by ads by the super PAC supporting Mr. Romney, Mr. Adelson’s $5 million donation to Winning Our Future was central to the revival of his candidacy in South Carolina, aides to him and Mr. Romney agreed.
But it was not certain what steps Mr. Gingrich was taking toward building his organization to meet the prowess of Mr. Romney’s. NYT