With his resounding victory overin Florida on Tuesday, showed a worried Republican base a side of himself that it has both longed for and feared that he lacked: the agile political street fighter, willing to mock, scold and ultimately eviscerate his opponent.
But if he has quelled doubts about his toughness, he also emerges from the Florida free-for-all and the three contests that preceded it carrying heavy new baggage.
Mr. Romney was savaged by Mr. Gingrich over his record at Bain Capital, softening him up for the coming Democratic effort to portray him as a heartless capitalist happy to fire people to enrich himself. His release of his tax returns, complete with details about a Swiss bank account, provided new facts for opponents seeking to cast him as out of touch with ordinary Americans.
And the very trait that propelled him in Florida — a willingness to descend into the muck and run a relentlessly negative campaign — distracted from his economic-themed argument against Mr. Obama while deepening his rift with some populist conservatives. Should Mr. Gingrich remain a viable enough candidate to stay in the race through the summer, as he vowed on Tuesday, Mr. Romney could be forced to maintain an angry edge that could undermine his appeal among moderate and independent voters — groups whose views of him, polls suggest, appear to have been harmed by the Florida melee.
“There are questions about his wealth and Bain, but he has not become an intensely polarizing figure yet,” said Alex Castellanos, a Republican strategist who worked on Mr. Romney’s presidential campaign in 2008. “The question is, will he become that?”
Mr. Romney himself seemed sensitive to the perception that his campaign has become locked in a bitter — and counterproductive — war of words with his leading Republican rival.
“I would like to spend more of our time focusing on President Obama,” he said in Tampa on Tuesday as voting was under way. “That’s ultimately what’s going to be essential to taking back the White House.”
His challenge is about to become even more complicated. As much as he would like to be punching and counterpunching with Mr. Obama, he must still contend with Mr. Gingrich, who even after his steep loss described the primaries as a two-man nomination fight across 46 more states.
Mr. Romney faces a classic dilemma in presidential politics: Going negative is never an appealing option, but the alternative amounts to unilateral disarmament and a much higher likelihood of defeat, especially against a rival like Mr. Gingrich who has little to lose.
“In primary politics, short-term gains are what matters, because if you don’t have the short-term gains, you won’t be around long enough to deal with the long-term problems,” said Peter A. Brown, assistant director of the Quinnipiac University Polling Institute.
Mr. Romney and his “super PAC” allies spent $15.4 million on television and radio advertising in Florida, three times what Mr. Gingrich and his supporters spent, in the most intensive assault of the Republican nominating contest: Over all, 92 percent of the ads from the candidates and outside groups were negative. In Florida, the outcome was what Mr. Romney needed — and possibly enough to all but eliminate Mr. Gingrich as a threat.
But if Mr. Romney has to engage in a long stretch of negative campaigning against Mr. Gingrich, the challenge will be to hit back hard enough that he does not leave himself exposed to another Gingrich comeback without undercutting his own image.
A candidate who comes across as attacking too viciously and personally risks turning off all but the most partisan voters. It happened with Bob Dole, most famously when he lost his temper during the 1988 presidential race, snapping that Vice President George Bush should “stop lying about my record.” That moment haunted him throughout the campaign. That may be one reason that Mr. Romney, in the glow of his Florida victory, praised his competitors and turned his attention to the president.
Mr. Romney has never been especially squeamish about negative campaigning. As jarring as his tone has seemed over the past 10 days, he has a long history of resorting to such tactics. (The exception was 2008, when Mr. Romney bowed out relatively early in the primary season.)
During his 2002 campaign for governor of Massachusetts, Mr. Romney ran biting commercials that portrayed his Democratic rival, the state treasurer Shannon O’Brien, as a basset hound asleep on the job as men walked off with bags of money. His poll numbers soon surged, and he pulled out an unexpected victory.
“He has learned along the way that this stuff works pretty well,” said Ms. O’Brien, who called the ads inaccurate and unfair.
This time around, Mr. Romney has been responding to scathing assaults from Mr. Gingrich, who in turn has said he went negative because the super PAC supporting Mr. Romney had unfairly attacked him in Iowa. Determined not to lose in Florida, Mr. Romney unleashed a wave of attacks on Mr. Gingrich’s finances, ethics and even stability — hammered repeatedly in TV commercials, conference calls, e-mails and speeches — that helped stoke the image of Mr. Gingrich as an “erratic” and “unreliable” leader.
The balance that Mr. Romney is trying to strike in his battle against Mr. Gingrich is one he also has to strike if he ends up facing Mr. Obama, whose aides have made clear that a general election campaign against him will be highly personal.
As if to underscore the point, Mr. Obama’s deputy campaign manager, Stephanie Cutter, took to Twitter to mock Mr. Romney for a line about Europe in his victory speech.
“If he dislikes it so,” she asked, “why is he betting against the American dollar with his own Swiss bank account?”
This article, "The Political Cost of Romney's Nasty Win in Florida," originally appeared at The New York Times News Service.