Taking part in a Republican presidential debate in Tampa, Fla., on Monday, Jan. 23, 2012, are (from left) former Pennsylvania Sen. Rick Santorum, former Massachusetts Gov. Mitt Romney, former House Speaker Newt Gingrich and Texas Rep. Ron Paul, as moderator Brian Williams of NBC News listens. (AP Photo/Paul Sancya)

Photo by: Paul Sancya

Taking part in a Republican presidential debate in Tampa, Fla., on Monday, Jan. 23, 2012, are (from left) former Pennsylvania Sen. Rick Santorum, former Massachusetts Gov. Mitt Romney, former House Speaker Newt Gingrich and Texas Rep. Ron Paul, as moderator Brian Williams of NBC News listens. (AP Photo/Paul Sancya)