Schieffer: Romney still must unify GOP

Mitt Romney closed out a decisive 14-point victory in Florida, the biggest contest thus far in the race for the GOP presidential nomination, but the former Massachusetts governor still must prove he can be a unifying candidate for Republicans.

As Bob Schieffer pointed out on "CBS This Morning," despite his big win Tuesday over chief rival Newt Gingrich, he failed to win over a majority of Republican voters.

"Although this was a huge win for him, there's still a number of people out there that are not satisfied with Mitt Romney," Schieffer said.

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As the election season moves forward, Romney will have to find a way to bridge the gap between the far right and the left of the Republican party if he is to defeat President Barack Obama in a general election, Schieffer said.

"It's going to be a very close race and it's going to have to be a united party. Right now, with all this negativity, I don't think you can say that it is."

Bob Schieffer is CBS News' chief Washington correspondent and moderator of "Face the Nation." For his full analysis of last night's Florida primary, watch the video above.