Newt Gingrich is a ladies’ man.

That is, he kicked butt, to use rival Rick Santorum’s phrase, among women voters in South Carolina’s Republican presidential primary. That was one of the biggest surprises of the evening, because women voters were widely expected to turn away from Gingrich.

“Republican women don’t vote for cheaters, period,” one Republican strategist in Washington said in an interview a few days before the South Carolina primary. The strategist, who requested anonymity to speak candidly, echoed long-held conventional wisdom and years of electoral results showing that women, in particular, are less likely to vote for political candidates with a history of marital infidelity.

Republican U.S. presidential candidate and former House Speaker Newt Gingrich celebrates backstage with his wife. Callista, and his supporters after his speech at his South Carolina Primary election night rally in Columbia, S.C. (Eric Thayer/Reuters)

Voters were reminded of that personal history just a few days before the primary, when a sensational interview aired on ABC with Gingrich’s second wife, Marianne, in which she accused Gingrich of asking her for an “open marriage” during the 1990s. The interview only heightened the expectation that Gingrich would not do well among women voters.

But something else entirely happened Saturday night in South Carolina: According to exit polls, Gingrich got nearly as much support from women as men. He won among married women, single women and evangelical women .He did beat other candidates by a somewhat larger margin among men, but he was tops among women as well, including 41 to 28 percent win over Romney among married women.

These results not only shed light on how Gingrich prevailed so widely in South Carolina; they also suggest that Gingrich may have dispensed with a topic long thought to be a huge weakness for him. That possibility may also force a rethinking by allies of former Massachusetts governor Mitt Romney, who have been attacking Gingrich on the issue of character for weeks.

Gingrich advisers interviewed Sunday said several factors likely played into Gingrich’s surge among women in South Carolina. First was the fact that Gingrich’s infidelity is old news for which Gingrich has repeatedly apologized. According to senior strategist Kevin Kellems, the very voters likely to hold infidelity against a candidate are the same voters more likely to consider forgiveness if they view the person as genuinely repentant.

“Everybody who’s watched us knows I am a 68-year-old grandfather,” Gingrich said on NBC’s Meet the Press Sunday. “ I have done things in my life that I regret, and I have had to go to God for forgiveness and reconciliation, but I have a great relationship with my wife, a great relationship with my children, a great relationship with my grandchildren, and at 68 I think I am the person best prepared to know how to get this country back on the right track.”

Lastly, Gingrich successfully changed the direction of the story by turning it into a referendum on the media, which he blamed for raising the topic of his marriages. He did so most notably in a feisty debate exchange Thursday in North Charleston, when Gingrich called CNN’s John King “despicable” for opening the debate with a question about Marianne Gingrich.

Republican women my colleague Melinda Henneberger interviewed in South Carolina on Friday morning were, she reported, even more supportive than men she interviewed of Gingrich’s handling of that debate question, saying it had only increased their admiration for him.

And Gingrich continued his attack on the media during his election-night speech in Columbia Saturday night and again Sunday on the national talk show circuit — a strong clue that he views it as a winning strategy and will keep talking about it in Florida in the coming days.

His team is also preparing — even looking forward to — the possibility that Romney’s allies will continue to hit him on character issues, a topic they believe will backfire.

U.S. Rep. Jason Chaffetz, for instance, a Romney supporter from Utah, went directly after Gingrich over character and family values on Sunday. “If we put up anything less than a Boy Scout, we’re gonna be in trouble,” he said. “You can’t cede strong family values to the Democrats. That’s supposed to be one of our hallmarks.”

“I don’t believe that voters in Florida will find that media bias trumps serial philandering,” he added. “I think when the reality of that question settles in for conservatives, they’re not going to stand for somebody who’s had trouble in these areas. I really don’t. I think voters in a rational moment will see how devastating and stupid that would be to hand that card to Barack Obama.”

Gingrich’s team said they welcome such attacks because they aren’t working.

“You had a 28-point turnaround in South Carolina,” said Rick Tyler, a spokesman for a pro-Gingrich super PAC. “It was just one attack ad after the next on TV. In politics, there’s reality, and there’s perception, and they missed both.”

Amy Gardner is a national political reporter for The Washington Post covering the 2012 Republican presidential field. Follow her on Twitter at @AmyEGardner.