Florida Republican debate: Winners and Losers The four politicians vying for the Republican nomination for president were on stage Thursday night for their final debate before voters in Florida decide who they want to compete against President Obama in November. The 19th sparring contest in front of the television cameras may be make or break time for one of the candidates. Mitt Romney came out swinging and when Newt Gingrich attacked, he hit back. Hard. Mitt Romney was more aggressive than he has been in prior debates. That may be because he senses the importance of changing the narrative for Tuesday's Floriday primary. Gingrich won an upset victory in South Carolina on January 21 after a stellar debate performance a week ago and is leading a number of national polls released this week, including an NBC News/Wall Street Journal poll released just before the start of Thursday's debate. Romney wants to stop that momentum in Florida and he now understands that political attacks are more often than not seen by voters for their response than what the original charge was. When I am shot at, I will return fire. I am no shrinking violet," Romney told CNN in a post-debate sideline interview, adding that he expects his performance "is going to give me the boost that I need" for Tuesday's vote. Santorum had his strongest debate performance yet. When Romney criticized President Obama's signature legislative achievement and said he would repeal the overhaul of the U.S. healthcare system, Santorum pointed out that the bill was modeled after similar legislation Romney championed as governor of Massachusetts and Romney would not be able to defend his law against Obama. What Governor Romney said is just factually incorrect. Your mandate is no different than Barack Obama's mandate. It is the same mandate" to force individuals to buy insurance. Blitzer asked the 76 year old Texas lawmaker if he would be willing to release his medical record because he would be the oldest person elected president if he were to win, Paul said he would "obviously" release it "because it's about one page, if even that long." He challenged the other candidates to a 25 mile bike ride in the heat of Texas. Gingrich even praised Paul's vigor on the campaign trail and said "he's in great shape" and would be "quite ready to serve if he's elected." Paul even managed to put Blitzer on notice for "age discrimination." Gingrich was flatter this debate than in past debates. And while he had some nice zingers to come back at Romney, he did not have a "knockout punch" that many said he needed to have to keep Romney from winning Florida on Tuesday. Gingrich received wild praise for his harsh attack on debate moderator John King last week and tried to double down on his strategy of attacking the host to build support. But his attack on moderator Wolf Blitzer for asking about Gingrich's apparent truce with Romney over the issue of taxes backfired. He called the question "nonsense" and suggested the four candidates on stage talk about "issues that relate to the governing of America" and leave the attacks for television interviews or other fora. The move was an attempt to be seen as taking the high-road, but when Romney took a jab at Gingrich for makings accusations he was not "willing to defend here," Gingrich went straight for the exit from the high road. Given that standard, Mitt, I did say I thought it was unusual. And I don't know of any American president who has had a Swiss bank account. Gingrich, Romney at each other's throats over immigration Gingrich, Romney agree to blame the Palestinians, Obama for lack of progress in the peace process Gingrich hints at making Marco Rubio VP Gingrich, Romney hit each other over involvement in Fannie Mae and Freddie Mac Romney tells Gingrich: I'd fire you for your moon proposal