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Santorum gets second wind with victories in Minnesota, Missouri and Colorado

Jeff Roberson / AP

Republican presidential candidate former Pennsylvania Sen. Rick Santorum speaks as his wife Karen, right, listens during a primary night watch party Tuesday, Feb. 7, 2012, in St. Charles, Mo.

Michael O'Brien, msnbc.com: Rick Santorum scored victories in Minnesota and Missouri nominating contests Tuesday night, winning him no actual delegates, but nonetheless blocking Mitt Romney's bid to keep alive a streak of victories in the Republican presidential primary.

Santorum won the distinction of having upset Romney in the last nominating contests before the campaign enters a three-week break before Michigan and Arizona's Feb. 28 contests. Tonight's results virtually ensure the GOP primary will extend through early March, while Romney will have to answer fresh questions about his ability to win over conservative primary voters.

Santorum had campaigned in Missouri and Minnesota -- along with Colorado, a third state hosting its nominating contest Tuesday evening -- while Romney, Newt Gingrich and Texas Rep. Ron Paul campaigned in Nevada.

See more images of Rick Santorum in our slideshow.