NORTH CHARLESTON, S.C. — The race for the Republican presidential nomination is veering toward South Carolina surreal.

Mitt Romney was stripped of his Iowa caucus victory Thursday, then was stung by Texas Gov. Rick Perry’s withdrawal and endorsement of Newt Gingrich, the former House speaker who was stunningly accused in turn by an ex-wife of seeking an open marriage so he could keep his mistress.

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EXIT: Texas Gov. Rick Perry pauses Thursday while announcing in North Charleston, S.C., he was suspending his Republican presidential candidate campaign and endorsing Newt Gingrich. AP

“Newt’s not perfect, but who among us is,” said Perry, abruptly quitting the race shortly before an evening debate and less than 48 hours before the polls open in Saturday’s first-in-the-South primary.

His decision to end a once-promising candidacy left Romney, Gingrich, former Pennsylvania Sen. Rick Santorum and Texas Rep. Ron Paul the remaining contenders in the race to pick a Republican to challenge Democratic President Barack Obama this fall.

Recent polls, coupled with Perry’s endorsement, suggested Gingrich was the candidate with the momentum and Romney the one struggling to validate his standing as front-runner. Whatever else the impact, the day’s events reduced the number of conservatives vying to emerge as Romney’s principal alternative.

The former Massachusetts governor had other challenges in a state where unemployment approaches 10 percent. He adamantly refused to explain why some of his millions were invested in the Cayman Islands, how much was there or whether any other funds were held offshore.

Under pressure from his rivals to release his income tax returns before the weekend — a demand first made by Perry in a debate on Monday — he told reporters it wouldn’t happen. “You’ll hear more about that. April,” he said.

Gingrich grappled with problems of a different, possibly even more crippling sort in a state where more than half the Republican electorate is evangelical.

In an interview scheduled to air on ABC News, Marianne Gingrich said her ex-husband had wanted an “open marriage” so he could have both a wife and a mistress. She said Gingrich conducted an affair with Callista Bistek — his current wife — “in my bedroom in our apartment in Washington” while she was elsewhere.

“He was asking to have an open marriage and I refused. That is not a marriage,” she said in excerpts released by the network in advance of the program.

Gingrich declined to respond to his ex-wife’s comments, telling reporters his two daughters from the first of his three marriages had sent a letter to ABC “complaining about this as tawdry and inappropriate.”

In fact, the letter made no such accusations. Instead, Kathy Lubbers and Jackie Cushman wrote ABC that anyone who has endured a failed marriage “understands it is a personal tragedy filled with regrets, and sometimes differing memories of events.”

The interview with the second of Gingrich’s two ex-wives and the evening debate weren’t the only political events in the run-up to the Saturday primary. Television commercials for the remaining candidates and their allies ran virtually without letup, generally designed to diminish each other’s support.

According to information made available to The Associated Press, targeted viewers in most regions of the state were watching an average of about six commercials a day paid for by Romney’s campaign and Restore Our Future, a group supporting him. Gingrich, Paul, Santorum and their backers raised the total higher.

Santorum ran commercials likening Romney to Obama; Gingrich’s cast the former speaker as the only candidate who could defeat the president this fall. In a sign of the shifting campaign, Restore Our Future stopped attacking Santorum so it could concentrate its fire on Gingrich.

Santorum, whose fortunes have ebbed since what appeared to be a narrow loss in Iowa, pronounced himself the winner there after all when state party officials in Des Moines announced he had finished 34 votes ahead of Romney instead of eight behind.

Iowa Republican chairman Matt Strawn said the party would not name an official winner because the results were so close and some votes couldn’t be counted. Results from eight of the state’s 1,774 precincts were not certified to the state party by Wednesday’s 5 p.m. deadline.

It was Strawn who had stepped before a microphone shortly before 2 a.m. in Des Moines on Jan. 4 to declare Romney the victor.

That announcement propelled the former Massachusetts governor into New Hampshire, where he breezed to victory in the opening primary of the campaign a week later.

He arrived in South Carolina the following day, front-runner then for sure, now more shakily so.

Perry’s withdrawal mimicked one earlier in the week by former Utah Gov. Jon Huntsman in that they both quit a few hours before a debate.

The similarities ended there, though. Huntsman endorsed Romney.

Perry had other thoughts, calling Gingrich a “conservative visionary who can transform our country.”

Echoing words Huntsman said of Romney, Perry said he and Gingrich had their differences.

And in saying the former speaker was not perfect, he sought to provide political cover of a type that might reassure South Carolina voters for whom religious values are important.

“The fact is, there is forgiveness for those who seek God and I believe in the power of redemption, for it is a central tenet of my own Christian faith,” Perry said.

His decision to withdraw set off a scramble among the remaining contenders for the allegiance of his supporters and donors, both in the state and nationally.

State Rep. Chip Limehouse of Charleston said he was expecting to speak by phone with both Romney and Gingrich later in the day before making up his mind.

“I’m looking and I really do think tonight’s debate will determine the next president of the United States. That’s how important it is,” Peeler said.

Perry’s exit marked the end of a campaign that began with soaring expectations but quickly faded. He shot to the head of the public opinion polls when he announced his candidacy last summer, but a string of poor debate performances soon led to a decline in support.

His defining moment came at one debate when he unaccountably could not recall the third of three federal agencies he has promised to abolish. He joked about it afterward but never recovered from the fumble.

In his farewell appearance as a candidate, he said he was bowing out of the 2012 campaign, seemingly a hint he would run again in four years if Republicans fail to win the White House this time.

An aide, Ray Sullivan was more explicit, telling reporters Perry hasn’t ruled out running for governor again or for the White House in 2016 if Obama is re-elected.

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