Published: Jan 30, 2012 5:20 PM EST
Updated: Jan 30, 2012 5:25 PM EST

POMPANO BEACH, Fla. (AP) - Mitt Romney said Monday he has overcome his South Carolina setback and returned to the Republican primary forefront by aggressively returning Newt Gingrich's fire and by presenting himself as a Washington outsider. Gingrich said Romney is "pretending he's somebody he's not."
    
Romney said that in the days leading up to the South Carolina's Jan. 21 primary, he was getting beaten up rhetorically by the former House speaker on a variety of fronts and says he didn't fight back very well. Now, Romney said, he has "pushed back" more effectively. He said he feels Florida's voters are responding to his charges that Gingrich benefited from his business relationship with the mortgage giant Freddie Mac at a time when the housing market in the state was taking a dive.
    
For his part, Gingrich argued that the former Massachusetts governor has bought "an amazing amount of ads" to leverage himself into better position for Florida's primary Tuesday, but said it won't work. "I think he's going to find this a long campaign," the former speaker said of his rival.
    
Gingrich said that on the big, philosophical issues, Romney "is for all practical purposes a liberal, I am a conservative."
    
"It's closing here in Florida," Gingrich said, "and I think the next 24 hours in going to make a big difference."
    
Romney said he believes he has reinvigorated his campaign through a combination of changes in his message and a change in campaign tactics. He said that Gingrich's charges that Romney is the establishment candidate aren't working.
    
"It's not selling here in Florida. ... He was able to get away with it in South Carolina. If there's anybody that's a Washington insider, it's Newt Gingrich."
    
A day before voting begins in Florida's Republican primary, Romney is running ahead of Gingrich in polls. Romney earned positive reviews during two debates and has put the former House speaker on the defensive over ethics and Freddie Mac.Â
    
"It's only when he can mass money to focus on carpet-bombing with negative ads that he gains any traction at all," Gingrich is complaining.Â
    
But instead of stepping back and refocusing on President Barack Obama - as he did in Iowa when it became clear that Gingrich had lost - Romney is ratcheting up his rhetoric and continuing his attacks until the very end. He hopes to close the Florida campaign strongly to push Gingrich as far back as possible.
    
Gingrich said Monday he was closing the gap between him and Romney in Florida. He said the Republican Party needed a "clear conservative" to run against Obama in the fall, and that there was very little difference between Obama and Romney when it came to their policies and politics, such as health care.
    
"Mitt Romney will have a very, very hard time trying to differentiate himself," Gingrich said.
    
 "His record is one of failed leadership," Romney had said of Gingrich at a rally in Sunday night in Pompano Beach, in South Florida. And Romney challenged Gingrich to "look in the mirror" to figure out why the former House speaker has fallen back in Florida.
    
"His record is one of failed leadership. We don't need someone who can speak well perhaps or can say things we agree with, but does not have the experience of being an effective leader," he said.
    
Aides say Romney's attacks are partially a response to increasingly angry rhetoric from Gingrich, who on Sunday called the former Massachusetts governor "somebody who is a pro-abortion, pro-gun-control, pro-tax-increase liberal."Â Gingrich also accused Romney of lying. "I don't know how you debate a person with civility if they're prepared to say things that are just plain factually false," Gingrich said.
    
Romney's campaign on Sunday fired back immediately, starting with the candidate and continuing with statements from top surrogates who cast Gingrich's assault as an unfair attack on Romney's character.
    
"Mitt Romney is man of impeccable character," said New Jersey Gov. Chris Christie. "It offends me that Newt Gingrich would attack the character of Mitt Romney."
    
Former Minnesota Gov. Tim Pawlenty called the attacks "over the line."
    
Romney's supporters particularly defended his anti-abortion credentials following Gingrich's attack. Gingrich allies are also running radio ads attacking Romney's record on the issue.
    
Florida Attorney General Pam Bondi called Romney a "champion for pro-life values" as she introduced him at the rally. Rep. Ileana Ros-Lehtinen offered a similar defense during an earlier rally with the Cuban American community in Hialeah.
    
In what has become a wildly unpredictable race, the momentum has swung back to Romney, who just last weekend was staggered by Gingrich's victory in South Carolina. Romney has begun advertising in Nevada ahead of that state's caucuses next Saturday, illustrating the challenges ahead for Gingrich, who has pledged to push ahead no matter what happens in Florida.
    
An NBC News/Marist poll published Sunday showed Romney with support from 42 percent of likely Florida primary voters, compared with 27 percent for Gingrich.
    
Former Pennsylvania Sen. Rick Santorum, trailing in Florida by a wide margin, skipped campaigning to be with his 3-year-old daughter, Bella, who was hospitalized. He planned to campaign in Missouri and Minnesota early this week.
    
Texas Rep. Ron Paul, who has invested little in Florida, looked ahead to Nevada. The libertarian-leaning Paul is focusing more on gathering delegates in caucus states, where it's less expensive to campaign. But securing the nomination only through caucus states is a hard task.
    
Romney has three events scheduled across the state Monday. He planned events in Jacksonville and the Tampa area. Gingrich has five planned events.Â
    
Romney appeared Monday morning on NBC's "Today" show and on Fox News Channel. Gingrich was interviewed on "CBS This Morning" and ABC's "Good Morning America."

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