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A strong showing by Romney has become even more critical as Gingrich has surged ahead in the Florida polls, leading 41% to the former Massachusetts governor's 32%.
Gingrich handily defeated Romney by 12 points in South Carolina, and the GOP race now looks to be on a prolonged trajectory.
On Monday, Romney was already blasting Gingrich, calling out his work at mortgage giant Freddi Mac, and even his authorship of history books.
Romney does expect to win Florida. Almost 200,000 absentee ballots have already been cast in the state, many of which it is believed favor Romney. Romney is also spending lavishly in the state, including a $2.3 million broadcast buy for ads made this week.
The fight between Romney and Gingrich will likely marginalize the other two candidates.
The gloves are off. Welcome to the GOP Octagon.