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NORTH CHARLESTON, S.C. — The race for the Republican presidential nomination took a turn toward the South Carolina surreal Thursday as Rick Perry dropped out, Newt Gingrich faced stunning allegations from an ex-wife and Mitt Romney struggled to maintain a shaky front-runner's standing.
An aggressive evening debate capped the bewildering day.
Former Sen. Rick Santorum played aggressor for much of the night, trying to inject himself into what seemed increasingly like a two-way race with little more than a day remaining until the South Carolina polls open on Saturday. He accused Gingrich and Romney of "playing footsies with the left" when it came to health care. Both men rejected the allegations.
The debate began a few hours after first word that Romney had been stripped of his Iowa caucus victory, only to be stung a few hours later by Perry's withdrawal and endorsement of Gingrich.
Gingrich, in turn, was accused by an ex-wife of seeking an open marriage so he could keep his mistress.
"Newt's not perfect, but who among us is," said Perry, abruptly quitting the race just before the first-in-the-South primary.
His decision to end a once-promising candidacy left Romney, Gingrich, Santorum and Texas Rep. Ron Paul the remaining contenders in the race to pick a Republican to challenge Democratic President Barack Obama this fall.
Nine hours after Perry exited one stage, the four remaining contenders walked onto another for a final pre-primary debate.
Gingrich angrily denounced the news media for putting his ex-wife front and center in the final days of the race. "Let me be clear, the story is false," he said. Santorum, Romney and Paul steered well clear of the controversy. "Let's get onto the real issues, that's all I've got to say," said Romney, although he pointed out that he and his wife, Ann, have been married for 42 years.
The audience gave Gingrich a standing ovation when he assailed the media, a reaction he can only hope is reflected in voter sentiment on Saturday.
All four remaining GOP candidates lustily attacked Obama, while Santorum in particular sought to raise his own profile.
Introduced to the audience at the outset, he mentioned his change of fortunes in Iowa, where an evident eight-vote defeat in caucuses on Jan. 3 was belated transformed into a 34-vote advantage — though the Iowa Republican Party did not declare a winner.
Santorum jabbed at both Gingrich and Romney, but seemed to focus more attention on the former. If Gingrich is the party nominee, he said, "you sort of have that worrisome moment that something's going to pop. And we can't afford that in a nominee."
In a reflection of the complex political dynamics of the race, first Gingrich and then Santorum challenged Romney over his well-documented switch of position on abortion. Once a supporter of a woman's life to choose, he now says he is "pro-life."
Gingrich didn't exactly question Romney's change in position, but he didn't embrace it, either, saying, "He had an experience in a lab and became pro-life."
Romney bristled. "I'm not questioned on character or integrity very often. I don't feel like standing here for that."
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 contenders vying to emerge as Romney's principal conservative 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, a position he renewed during the debate to jeers from the audience.
Gingrich pursued an approach Perry used in the earlier debate.
"If there's anything that's in there that's going to help us lose the election, we should know before the election. If there's not, why not release it?" he said.
Gingrich released his own tax return during the day, reporting that he paid the IRS $613,517 in taxes on more than $3.1 million in income. He also donated about 2 percent of his income to charity.
His effective tax rate, roughly 31.6 percent of his adjusted income, was about double what Romney told reporters earlier this week he had paid.
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.