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It was a very, very good day for Republican hopeful Rick Santorum.

It was a bad day for presumptive GOP front-runner Mitt Romney.

Santorum's cast his wins in Missouri, Minnesota and Colorado as a victory for a purer form of conservatism than Romney has offered.

Romney shrugged off his poor showing, but his losses Tuesday laid bare his stubborn weakness just when it looked as if his party was beginning to embrace him.

Bringing up the rear of the Santorum surge: Newt Gingrich, the former House speaker who mostly skipped the contests and finished at or near the back of the pack in all three states.

Santorum praised the voters across the nation's midsection without a deafening TV air war that Romney has dominated: "Tonight, we had an opportunity to see what a campaign looks like when one candidate isn't outspent 5- or 10-to-1 by negative ads impugning their integrity and distorting their record. This is a more accurate representation, frankly, of what the fall race will look like," a jubilant Santorum told a cheering crowd in St. Charles, Mo.

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But it was far from clear that the former Pennsylvania senator, who has a post office box for a campaign headquarters and relies on volunteers to handle scheduling, can quickly turn the momentum into the millions of campaign dollars he would need to overcome Romney. Still, he looked past the nomination fight.

"I don't stand here to be the conservative alternative to Mitt Romney, I stand here to be the conservative alternative to Barack Obama," Santorum said. On health care, cap and trade and the Wall Street bailout, he charged, "Mitt Romney has the same positions as Barack Obama."

In Denver, Romney congratulated his rival. The revived questions about Romney's appeal with conservatives at the party's core were even sharper in light of his aggressive push to court them in recent days. Santorum's shoestring candidacy thrived. And the GOP nomination fight many in the party hoped would resolve itself after Super Tuesday now threatened to rumble past March 6 — while Obama watches from his presidential perch in the White House, and waits.

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"This was a good night for Rick Santorum," Romney told supporters in Denver on Tuesday night. He offered a bit of forced optimism: "We'll keep on campaigning down the road, but I expect to become our nominee with your help."

Romney added, "When this primary season is over, we're going to stand united as a party behind our nominee to defeat Barack Obama."

He wasn't the only loser.

On the first day of multi-state voting, the trio of contests exposed a glaring deficiency for Gingrich.

The former House speaker lacked the resources and organization to compete just as he's trying to project strength heading into the Super Tuesday elections. He made only minimal efforts in the three states that voted and stayed out of sight as the results rolled in. Gingrich is focusing on Ohio, where early voting has begun in the March 6 primary.

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Texas congressman Ron Paul, meanwhile, reveled in his second-place win in Minnesota and vowed to keep collecting delegates to take to the GOP's national convention this summer.

To be fair, Tuesday's contests will have little bearing on the race for delegates. Missouri's nonbinding primary in particular was little more than an extensive warm-up routine. The state will hold an official caucus in March.

But even symbolic victories can produce or slow down momentum.

Romney's camp began downplaying the results hours before the voting began. Rich Beeson, his political director, released a memo earlier in the day noting that even Sen. John McCain lost 19 states on the way to capturing the GOP presidential nomination in 2008.

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Following Maine's low-profile caucuses, which conclude Saturday, the candidates will have an extended lull. Beeson recently noted that momentum would be vital heading into the 17-day period without an election, something he likened to a grand canyon with no precedent in modern presidential politics.

"If you don't have momentum and resources coming into it, it's going to be hard to have momentum and resources coming out of it," Beeson said.

That was a week before he realized his boss would suddenly see his momentum disappear.

Based on reporting on the Associated Press. 

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