Tonight’s the last debate for GOP candidates for president before the South Carolina primary on Saturday, and the race where former Massachusetts Gov. Mitt Romney was expected to capture his third win in a row all of a sudden is being shaken up.

That’s because Romney no longer is the victor in the Iowa caucuses. Where he once was thought to have beaten former Sen. Rick Santorum by a handful of votes Iowa officials now officially have declared it a tie – with Santorum actually a handful of votes ahead.

Then there was the move today by Texas Gov. Rick Perry to drop out of the race and throw his support behind former House Speaker Newt Gingrich – potentially giving his so-far No. 2 campaign at least a bit of a boost.

A Politico survey released today said 37 percent of the GOP primary votes in South Carolina say they are backing Romney, some 30 percent are behind Gingrich, 11 percent are behind Rep. Ron Paul of Texas, 10 percent behind Santorum, and others undecided.

The CNN/Southern Republican Presidential Debate debate, hosted by John King, is at 8 p.m. ET. Coverage is at and other sites.

Further expected to complicate the race is a pending interview on ABC by Marianne Gingrich, the former House speaker’s former wife. Much of the information that appears to be forthcoming already has been uncovered because of Gingrich’s high profile political life.

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