MIAMI - Mitt Romney strode into the final 48 hours of the pivotal Florida Republican primary campaign with the confidence of a resurgent front-runner, predicting he'll win in Tuesday's voting while looking ahead to future contests.
His main rival Newt Gingrich hustled around the state, trying to rekindle the energy that lifted him to victory in the South Carolina primary on Jan. 21. He acknowledged the possibility he could lose here but vowed to stay in the contest, fighting Romney all the way to the party's national convention in September.
Outspent 3-1 on television advertising in Florida during the campaign's closing week, Gingrich was working to raise his profile on the cheap in conversations with reporters on Saturday. He appears on two nationally televised Sunday talk shows.
Gingrich has been under heavy attack from Romney and allies of the former Massachusetts governor. Romney had spent the past several days, including during two Florida debates, sharply criticizing Gingrich's discipline, temperament and ethics during and after his time as the speaker of the House of Representatives in the 1990s.
Romney changed his line of attack on Saturday to refocus his criticism on President Barack Obama.
"He's detached from reality," Romney said. He criticized Obama's plan to cut the size of the military and what he described as the administration's weak foreign policy.
Gingrich's South Carolina momentum has largely evaporated in the advertising assault by Romney's campaign and the pro-Romney group called Restore Our Future. They have spent some $6.8 million in ads criticizing Gingrich in the Florida campaign's final week. Polls show Romney solidly ahead.
By contrast, Gingrich was spending about $700,000, and Winning Our Future, a group backing him, an additional $1.5 million. That was about one-third the amount for the pro-Romney tandem.
Gingrich planned to campaign Sunday in central Florida.
Romney had a series of rallies planned for south Florida. He was also looking ahead to the next-up Nevada caucuses and was airing ads in that state ahead of the Feb. 4 contest.
Gingrich sought to regain momentum with the endorsement of Herman Cain, a tea party favourite and former presidential hopeful whose White House effort foundered amid sexual harassment allegations.
Gingrich has been put on the defensive under Romney's withering attack. Gingrich responded by describing the former Massachusetts governor as "dishonest" and questioning his Republican credentials.
His pledge to stay in the race suggests Republicans could be in for a long winter and spring if money continues to flow into Gingrich's campaign.
A third Republican contestant, former Pennsylvania Sen. Rick Santorum, has made an effort to campaign in the Sunshine State but trails Romney and Gingrich by a wide margin. He cancelled his Sunday events after his 3-year-old daughter Bella was hospitalized. She suffers from a serious genetic condition.
Texas congressman Ron Paul has invested little in the Florida race and is looking ahead to Nevada.