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Washington (CNN) -- Mitt Romney got hit with a double whammy Thursday. He's no longer the winner in Iowa, and Rick Perry's withdrawal means the anti-Romney conservative vote is suddenly a little less splintered.
The big winner: Newt Gingrich. The former House speaker -- endorsed by Perry -- is the conservatives' man of the hour, and finds himself at the head of the "anybody but Mitt" pack.
If you thought the GOP race was headed toward a quick knockout finish in South Carolina or Florida, think again. The odds of an extended GOP nomination fight just increased dramatically.
"The news about the Iowa caucuses and Rick Perry dropping out should give Gingrich a little bit more ammunition in his challenge to Romney," Brown University political scientist Wendy Schiller told CNN. "Because Gingrich is so far ahead of Santorum in the South Carolina polls, he can use Santorum's Iowa win as an endorsement for the conservative wing of the party's clout in determining the nominee, without worrying about enhancing Santorum's position" in the Palmetto State.
The initial results from Iowa on January 3 gave Romney a paper-thin margin of eight votes over Santorum. The final certified results show Santorum ahead of Romney by 34 votes. Romney can no longer claim to be the first non-incumbent Republican in history to win both Iowa and New Hampshire -- a blow to a candidacy built partly on the twin pillars of electability and inevitability.
Santorum is lower on funds than his rivals and trails both Romney and Gingrich in the South Carolina horse race -- a reality that leaves him poorly positioned to capitalize on the belated news of his apparent Iowa victory. Gingrich, however, is now nipping at Romney's heels in polls in the state, and is coming off a strong debate performance Monday night. Debates have been the former speaker's ace in the hole so far, and he'll have another bite at the apple when the candidates meet Thursday evening at a CNN/Southern Republican Leadership Conference showdown in Charleston.
This "really puts the pressure on Romney," said CNN Chief Political Correspondent Candy Crowley. "I don't think he can have an off debate. ... He has to be Mitt Romney at his best."
Political analysts say Romney had a relatively weak debate performance on Monday. He appears to have been off-message since that time, struggling with questions about his wealth and tax returns -- uncomfortable topics for the former venture capitalist.
For his part, Perry was sitting at mid-single digits in most South Carolina polls. If his endorsement of Gingrich adds another few points to the former speaker's tally on Saturday night, it could prove to be the difference between a first and second place finish.
During his withdrawal speech Thursday morning, Perry stressed that Gingrich "is not perfect." But, he asked, "Who among us is? 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 Christian faith."
Perry's comments, noted CNN Chief Political Analyst Gloria Borger, were aimed squarely at evangelical voters, often the dominant force in South Carolina Republican politics. Gingrich's past marital difficulties have been a recurring storyline in the nomination fight, and are believed to be hurting him with many of the Christian conservatives who had been backing the Texas governor.
"I think Rick Perry was specific in (his) purpose on this," Borger said. His decision to mention the importance of redemption "sent a signal to those (evangelical) voters that it's OK" to shift their support to Gingrich.
If Gingrich can pull off a win in South Carolina, the first three states to vote will have delivered first-place finishes to three different candidates. "Then it's on to Florida with a giant question mark," said CNN Chief National Correspondent John King. Florida voters are scheduled to go to the polls on January 31.
If Romney hangs on in the Palmetto State, you "can't say (the nomination is) his, but he's on a pretty good path," King added.
Over the long term, Romney's money and machine will be extremely tough for Gingrich or anyone else to overcome. But a close finish Saturday night at least guarantees "another punishing week for Romney on the campaign trail" heading into Florida, Schiller said.