Romney: Gingrich's attacks "toughened us up"

Updated at 10:14 a.m. ET

Reclaiming frontrunner status from former House Speaker Newt Gingrich, former Massachusetts Gov. Mitt Romney said on "CBS This Morning" Wednesday that campaigning against Gingrich in the Republican race for president has made him a tougher candidate.

Romney handily won Tuesday night's Florida primary, bouncing back from a loss to Gingrich a week and a half ago in South Carolina that appeared to show the Georgia Republican gaining momentum. But Romney went on the attack in the Sunshine State, attacking Gingrich on the stump, in strong debate performances and over the airwaves with a flood of television advertisements.

"The attacks that have come from him have probably toughened us up and helped us learn how to respond," Romney told Charlie Rose. "Clearly, what Barack Obama comes with will be a lot more money, even more vitriolic than what we faced so far, but we're prepared."

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Seizing an opportunity, Romney attacked Gingrich's portrayal of himself as a conservative in the mold of President Ronald Reagan.

"The argument that he somehow is the Reagan conservative, I think, just doesn't square with the facts," said Romney. "This is a guy who was arguing for cap-and-trade legislation by sitting on the sofa with Nancy Pelosi. This is a fellow who called Paul Ryan's bold plan for saving Medicare, he called it right-wing social engineering. His big, bold idea here in Florida has been to build the space station or a colony on the moon and making it the 51st state.

"These are not conservative ideas; they're big, expensive ideas. I think that he has had a very difficult time convincing people that he really is the conservative leader in our party. ... I've got the conservative record he wishes he had."

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Romney said he didn't begrudge Gingrich for not placing a congratulatory phone call to him Tuesday night, a gesture Romney said was made by former Pennsylvania Sen. Rick Santorum and Texas Rep. Ron Paul, who placed third and fourth in the primary respectively.

"I don't worry about that, I gotta be honest with you," said Romney. "I'm very pleased that Ron Paul and Rick Santorum and I have spoken after each race, and frankly I called the speaker after the race in South Carolina, congratulated him. He welcomed that congratulations, but he hasn't chosen to call me on any of the three of the prior contests."

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Despite the boost of momentum that comes with his latest victory, Romney expressed cautious optimism when asked if the battle for the GOP nomination was over.

"Nothing is certain in politics," said Romney. "You just can't predict precisely what's going to happen, but I'm in a much better spot than I was 10 days ago."

Above, watch the full interview with Mitt Romney