Just in case the 2012 Republican primary race hasn’t already had enough twists and turns – welcome back, Rick Santorum.

Rick Santorum pulled off an upset victory in Colorado, capping a three-win night on Tuesday. He defeated Mitt Romney in a state where the former Massachusetts governor was expected to glide to victory.

With 100 percent of precincts reporting, Santorum eked out a win with about 40 percent to Romney’s 35 percent. Newt Gingrich came in third with 13 percent, followed by Ron Paul with 12 percent.

Santorum’s success in Colorado’s caucuses amounted to his third triumph of the night and a major boon to his previously floundering presidential campaign. The former senator racked up wins in both Minnesota and Missouri – his first wins since his first-place finish in Iowa’s caucuses more than one month ago.
“Tonight was not just a victory for us,” Santorum said in St. Charles, Mo., before Colorado’s final tallies had been announced. “Tonight was a victory for the voices of our party.”

The close finish followed a hair-raising counting of the votes that extended late into the night and mirrored the contest one month earlier in Iowa, where Romney and Santorum fought to a near-draw. Like in Iowa, the tally in Colorado see-sawed back and forth, variously showing Santorum and Romney in the lead.

None of the contests held Tuesday were binding on delegates, but the surprise sweep from Santorum instantly upended assumptions that he had faded in the GOP race and that the nomination had been all but locked by Romney.

Santorum’s conquest in all three races amounted to a devastating blow to Romney. The expectations had been high for Romney to win handily in Colorado, where he has been aggressively campaigning in the three days since he won Nevada’s caucuses, and where his campaign has worked for months to establish a solid ground game.

Santorum campaigned in Colorado, but focused most of his attention on Minnesota and in Missouri, where Newt Gingrich was not on the ballot and he stood a better chance to claim the mantle of the conservative Romney alternative.

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