PORT ST. LUCIE, Fla. (AP) - On the weekend before the pivotal Florida primary, Newt Gingrich vowed Saturday to stay in the race for the Republican presidential nomination until the national convention this summer even if he loses Tuesday's vote. Front-runner Mitt Romney poured on the criticism of his rival in television ads airing across the state.
Gingrich's pledge, followed several hours later by an endorsement from campaign dropout Herman Cain, raised the prospect of an extended struggle inside the party as Republicans work to defeat President Barack Obama in the fall. "You just had two national polls that show me ahead," he said. "Why don't you ask Gov. Romney what he will do if he loses" in Florida.
The former Massachusetts governor countered a few hours later while in Panama City. "I think we are going to win here, I sure hope so," he said.
As the two rivals made their appeals to Hispanic, Jewish and tea party voters, veterans of the armed forces and others, all known indicators pointed to a good day for Romney in the primary.
He and his allies held a 3-1 advantage in money spent on television advertising in the race's final days. Robust early vote and absentee ballot totals followed a pre-primary turnout operation by his campaign. Even the schedules the two men kept underscored the shape of the race - moderate for Romney, heavy for Gingrich.
Campaigning like a front-runner, Romney made few references to Gingrich. Instead, he criticized Obama's plans to cut the size of the armed forces. "He's detached from reality," the former Massachusetts governor said.
"The foreign policy of "pretty please' is not working terribly well," he added. Romney said he wants to add 100,000 troops, not cut them.
If his personal rhetoric was directed Obama's way, the television commercials were trained on Gingrich, whose victory in last Saturday's South Carolina primary upended the race for the nomination. A new ad released as the weekend began is devoted to the day in 1997 when Gingrich received an ethics reprimand from the House while serving as speaker and was ordered to pay a $300,000 fine.
Nearly the entire 30-second ad consists of NBC News anchor Tom Brokaw's nationally broadcast description of the events on the evening news. "By an overwhelming vote, they found him guilty of ethics violations; they charged him a very large financial penalty, and they raised - several of them - raised serious questions about his future effectiveness," Brokaw said that night, and now again on televisions across Florida.
Both NBC and the former newsman registered objections. The network called on the campaign to stop using the footage and Brokaw said in a statement, "I do not want my role as a journalist compromised for political gain by any campaign."
A Romney adviser, Eric Fehrnstrom, said the campaign wasn't likely to stop running the ad. "We believe it falls within fair use," he said. "We didn't take the entire broadcast; we just took the first 30 seconds."
Whatever its impact, the ad represented part of a barrage that Gingrich could not match.
A second Romney ad said Gingrich had "cashed in" as a Washington insider while the housing crisis was hitting Florida particularly hard.
Figures made available to The Associated Press showed Romney was spending $2.8 million to air television commercials in the final week of the Florida campaign. In addition, a group supporting him, Restore Our Future, was spending $4 million more, for a combined total of $6.8 million.
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.
Officials said the total of absentee and early vote cast approached 500,000, about 200,000 of them before Gingrich won in South Carolina last weekend.
Cain's endorsement came at a GOP dinner in West Palm Beach. The business executive led briefly in the polls last fall, then cratered and dropped out of the race after he was accused of sexual harassment and marital infidelity.
In supporting the former speaker, he followed an example set by Texas Gov. Rick Perry, who bestowed his endorsement a few days before the South Carolina primary.
Gingrich seemed in good humor during the day, despite the obstacles in his way. He joked with reporters that they had missed an example of his grandiosity - a charge that one rival, former Pennsylvania Sen. Rick Santorum, had used in a recent debate - when they didn't see him hold a golf trophy on display at the PGA Library.
Gingrich also turned aside one opportunity to criticize Romney, answering a question by saying, "I want to talk about defeating Obama."
But his tone seemed to change after he said he wasn't happy with his performances in a pair of debates during the week, and was asked to explain.
"You cannot debate somebody who is dishonest. You just can't," he said, referring to Romney.
Referring to one answer the former Massachusetts governor had given, Gingrich said it was not true that Romney had always voted for a Republican when one was on the ballot.
"That in fact he could have voted for George H.W. Bush or Pat Buchanan the same day and he chose the Democratic primary, he voted Paul Tsongas, the most liberal candidate. The same year he gave money to three Democrats for Congress," he added, referring to the 1992 campaign.
"Now there's no practical way in a civil debate to deal with somebody who is that willing to say something that is just totally dishonest."
Romney poked fun at Gingrich's debate performances.
"This last one Speaker Gingrich said he didn't do so well because the audience was so loud. The one before he said he didn't do so well because the audience was too quiet. This is like Goldilocks, you know, you've got to have it just right.
"When I debate the president, I'm not going to worry about the audience, I'm going to make sure that we take down Barack Obama and take back the White House."
The two other contenders, Santorum and Texas Rep. Ron Paul, have conceded Florida and did not campaign in the state during the day.
Associated Press reporter Steve Peoples in Panama City contributed to this report.