Romney wins big, but not big enough to end nomination race

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TAMPA, Fla. — Mitt Romney didn't just win in Florida, he won big.

But not big enough to end what has become a bitter two-man race for the GOP presidential nomination, between Romney and former U.S. House speaker Newt Gingrich.

In his victory speech, Romney sought to reassure Republicans that the battle isn't going to hurt the party's chances of defeating the Democratic candidate, President Barack Obama, in November.

"A competitive primary does not divide us. It prepares us," Romney told a cheering and flag-waving crowd of supporters jammed into a Tampa convention center ballroom. "And we will win."

He made a point of congratulating his opponents on "a hard-fought campaign," but did not refer to Gingrich or the other two candidates still in the race, Texas Rep. Ron Paul and former Pennsylvania Sen. Rick Santorum

Instead, after days of going on the offensive against Gingrich in campaign speeches and in television commercials that filled the Florida airwaves, Romney pivoted in his victory speech to target Obama, offering new, harsher jabs at the president.

"Leadership is about taking responsibility, not making excuses," Romney said. "Mr. President, you were elected to lead, you chose to follow, and now it's time for you to get out the way."

But Romney isn't likely to let up on Gingrich in the upcoming races, starting with Nevada's Republican caucuses on Saturday.

He's "going to defend himself and he will continue to draw the distinctions," said Rep. Jason Chaffetz, R-Utah, one of Romney's key surrogates. "If you don't answer the criticism, it runs a chance of sticking."

That's what Romney found out in South Carolina, where he'd hope to wrap up the nomination earlier this month, but ended up losing to Gingrich amid attacks on his business dealings and personal wealth.

In Florida, Romney shifted his strategy to go after the former U.S. House speaker's ties to the troubled government-backed mortgage lender Freddie Mac. Gingrich has vowed to keep the race going through the party's nominating convention in August.

Chaffetz, who will rejoin the campaign Thursday in Nevada, said Romney "was very good at showing the passion and the fight in his belly. I think people wanted to see that."

University of Utah Hinckley Institute of Politics head Kirk Jowers, a longtime Romney adviser, said Florida sends a message to voters in the upcoming primary states.

"South Carolina seemed to call in to question whether he had the fight necessary to take on Obama and his billion dollars," Jowers said. "There's no question that Florida answered Mitt is ready, willing and able."

Jowers said Romney was not "unnecessarily hostile and I don't see him changing that. But he won't let someone like Newt Gingrich ambush him again."

David Damore, a political science professor at the University of Nevada, Las Vegas, said he expects Romney "to keep the boot down on Gingrich" in Nevada. "I think he wants to finish off Gingrich," Damore said.

While Romney is seen as the favorite in Nevada because of the large number of voters who share his Mormon faith, Damore said there is "a significant anti-Romney vote out there looking for a place to go."

Romney needs to be careful not to be seen as too aggressive, University of South Florida political science professor Susan MacManus said.

"That ends up biting you," she said. Romney would do well to "keep Gingrich off guard a little bit. He doesn't have to do a lot of it."