South Carolina primary: As polls close, Gingrich leads

Former House speaker Newt Gingrich is leading rival Mitt Romney in the South Carolina primary, according to CBS News estimates based on analysis of early exit polls. Rick Santorum and Ron Paul are battling for third place at this early stage.

The estimate comes just after the Palmetto State polls closed at 7:00 p.m. Eastern Time. 

Live Election Results for South Carolina

If Gingrich ends up with a victory in South Carolina it will be due in large part to his strong performance in two debates in the state this week. Nearly two in three GOP primary voters said the debates played an important role in their decision, and more than half (53 percent) made up their minds in the last few days, according to early exit poll data.

Among these late-deciders, Gingrich was the clear favorite: 45 percent backed him, compared to 24 percent for Romney and 19 percent for Santorum.

And among the 64 percent who said the debates were an important factor, 50 percent backed Gingrich, while just 23 percent were backing Romney. The former Massachusetts governor led among voters who said the debates were not an important factor in their vote, 41 percent to Paul's 21 percent and Gingrich's 18 percent.

The exit poll data show Gingrich winning among white evangelicals, who made up 63 percent of the electorate. Forty-four percent backed Gingrich, while 23 percent backed Romney and 19 percent backed Santorum. Gingrich also held a strong lead over Romney among men (41 percent to 28 percent), conservatives (43 percent to 26 percent) and Tea Party supporters (43 percent to 28 percent). Romney led narrowly among non-Tea Partiers and moderates.

South Carolina GOP primary exit polls

Nearly half said the most important quality in a candidate is that he can beat President Obama in November; among this group, 49 percent were supporting Gingrich and 41 percent were supporting Romney. Gingrich also led Romney among the 61 percent who called the economy the most important issue, 39 percent to 35 percent.

Independents, a group that made up about one fourth of the electorate, split between Gingrich (31 percent), Paul (26 percent) and Romney (25 percent).

A Gingrich victory in South Carolina would recast a race that Romney had been dominating as recently as one week ago, when he had been declared the winner of the first two contests and was leading the polls in South Carolina. The past week has been one of the worst of Romney's campaign: He stumbled in the debates, at one point receiving a smattering of boos for equivocating over how many years of his tax returns he would release, and was stripped of his Iowa win after a recount. Romney, whose net worth is estimated at up to a quarter of a billion dollars, also acknowledged that his effective federal income tax rate is roughly 15 percent, lower than the rate paid by most Americans.

Gingrich, meanwhile, offered up two strong debate performances, including one on Thursday in which he earned a standing ovation for the way he swatted away a question about allegations from his ex-wife. The charges from Marianne Gingrich, who said Gingrich asked her for an open marriage involving the woman who would later become Gingrich's third wife, did not appear to discourage South Carolina Republicans from supporting the former House Speaker.

For Santorum, a poor finish in South Carolina could mean the end of his campaign. Santorum rose from obscurity to eventually be declared the winner in Iowa, but he appears to have been unable to best Gingrich in the battle to become the consensus conservative alternative to Romney in South Carolina, and he may not have the resources going forward to compete in the January 31 contest in Florida, a large state with expensive rates for television ads.