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."