(CNN) -- The South Carolina Republican presidential primary is often a free-for-all, but this year's contest probably sets a new standard for volatility. Not surprisingly, Palmetto State GOP insiders see a close finish in the primary Saturday between former Massachusetts Gov. Mitt Romney and former House Speaker Newt Gingrich, according to a CNN survey. Less than 48 hours before voters would go to the polls, they were buffeted by a sudden announcement from Texas Gov. Rick Perry that he was withdrawing from the Republican presidential race and endorsing rival Gingrich. And as Perry was dropping out, the political world was buzzing with reports that Gingrich's second wife, Marianne, said that her then-husband proposed an "open marriage" before they divorced. Then, a fiery Gingrich struck back at the opening of the CNN debate in Charleston, attacking the "liberal media" for bringing up the story in the first place.
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CNN asked 42 South Carolina GOP insiders about Saturday's primary
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Surveys taken both before and after Rick Perry's withdrawal from race
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Romney and Gingrich are in a close race, the group says, closer since Perry left
"Romney's supporters seem to be firmly behind him at this point, while Gingrich could still gain or lose support depending on how things shake out over the (final) days," said one @placeholder insider.