Mitt Romney took an early swipe at resurgent GOP primary candidate Newt Gingrich, labelling him a ‘lifelong politician,’ a move that underscored the threat Romney’s campaign sees in Gingrich. As Philip Rucker and Amy Gardner reported:

Romney on Tuesday lodged his first attack on his surging rival, Newt Gingrich, by labeling the former House speaker “a lifelong politician” and suggesting he lacks credibility on the economy.

Asked by Fox News’s Bret Baier in an interview Tuesday whether Gingrich could beat President Obama, Romney said: “I think to get President Obama out of office, you’re going to have to bring something to the race that’s different than what he brings.”

“He’s a lifelong politician. I think you have to have the credibility of understanding how the economy works. And I do. And that’s one reason I’m in this race.”

Among the Republicans running for president, Romney said that he believes he has the best shot “by far” of defeating Obama. He called Gingrich “a good man,” but highlighted the differences in their backgrounds.

“He spent his last 30 or 40 years in Washington,” Romney said. “I spent my career in the private sector. I think that’s what the country needs right now.”

Gingrich fired back in an interview following a town hall meeting tonight at the Newberry, S.C., Opera House.

“You’re talking to a guy who was dead in June. I’m now being attacked by the former frontrunner,” he exulted.

He also defended his economic experience. “I would point out as a matter of fact, having participated in the development of supply-side economics with (former Rep. Jack) Kemp, having campaigned with Reagan on it in 1980, having helped pass it in ‘81 and having gone through the recovery in the ‘80s and having 11 million jobs created over four years as speaker, I may have some knowledge of the economy.”

After Mitt Romney’s 2008 candidacy collapsed following a strong early campaign, he is taking a different tack in his run to the Republican Convention in 2012. As Dan Balz explained:

Four years ago, Mitt Romney was done in when he ended up fighting a multi-front battle against different opponents. This year, it has been his lucky fate to escape any real battles from any specific opponent. That will soon change.

Romney’s 2008 strategy, built on the assumption that someone not nationally known could take the nomination only by winning early and often, was based on some sound assumptions. What he didn’t anticipate was how the campaign would unfold against him.

Remember what happened. He started early to organize states like Iowa and New Hampshire. He started airing television commercials in the spring of 2007. He won the Iowa straw poll and went to the front of the line as the favorite to win the caucuses. He took the lead in New Hampshire, thanks to the implosion of John McCain’s campaign in the summer.

At that point, Romney’s strategy seemed to be working. Instead, it led to his unraveling.

Fast-forward to this year and see the differences. Romney’s campaign advisers say their strategy is based on two major assumptions: No state will determine Romney’s fate, and delegates matter.

Others will have a different view. If there is one state that matters to Romney, they will argue, it is New Hampshire. A loss there could be crippling, especially if it follows a loss in Iowa. Other favorites in New Hampshire have lost the state-- Walter Mondale in 1984, Bob Dole in 1996, George W. Bush in 2000--and survived to win the nomination. The difference is that each of those three had won Iowa.

Whether Romney is ahead or behind in the delegate count, many analysts see the Florida primary as critical to Romney’s chances at the nomination. As AP reported:

If there’s any Republican presidential candidate who can afford to spend precious time and money focusing on winning in Florida, it’s the one who campaigned in the state Tuesday.

Florida is the only early primary state Mitt Romney plans to visit this week, little more than a month before voters start weighing in on the GOP nominating fight.

Depending on how he performs in earlier contests in Iowa, New Hampshire and South Carolina — all three are still uncertain — Florida represents a chance for Romney to either seal the nomination or an opportunity to revive what likely would become, if he’s lost three times, a struggling campaign.

Romney spent all day in Florida, attending several fundraisers and holding public events in Miami and Tampa.

Unlike his rivals, Romney has the resources to compete aggressively here. He had nearly $15 million at the end of October and has spent little of it — a war chest that would allow him to buy expensive TV ads across Florida’s 10 media markets. He has national name recognition from his 2008 bid, an asset his team believes will give him a significant advantage over lesser-known rivals in a large state where retail politicking alone doesn’t cut it. And he’s kept in good touch with the support and fundraising network he built last time around, an effort that’s shown through as he’s picked up endorsements from many of the state’s top Republicans, including former Sens. Mel Martinez and Connie Mack.

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