The four remaining major Republican candidates for president square off in Tampa, Florida, in the 18th debate of the 2012 season.

Newt Gingrich is surging and Mitt Romney hopes to rebound as Rick Santorum and Ron Paul search for a way to break into the conversation before Florida Republicans vote Jan. 31.

There have been two primaries and one caucus and Santorum, Romney and Gingrich have each won once. Ron Paul has a long-term strategy that stretches well into February.

ABC News and Yahoo News will offer live analysis and commentary of the GOP debate sponsored by NBC.