Rick Santorum had a breakthrough night Tuesday, winning GOP (The nickname of Republican Party) presidential contests in Missouri, Minnesota and Colorado, all of which is expected to breathe life into his struggling campaign and slow Mitt Romney's march to the Republican presidential nomination. Santorum solidly defeated Romney in Minnesota and Missouri, and he narrowly edged the former Massachusetts governor in Colorado, according to state GOP officials. The victories mark a sharp turnaround for the former Pennsylvania senator, whose candidacy had been sputtering after he failed to capitalize on his narrow win in Iowa last month. Santorum's wins across the Midwest Tuesday could bestow new legitimacy on his insurgent efforts and boost his fundraising in the critical period before next month's major contests. Santorum now appears to pose a more serious threat not only to Romney, but also to Gingrich, who had been positioning himself as the logical alternative to Romney. Santorum staked his own claim on Tuesday. "Conservatism is alive and well," he told supporters at his election night party in Missouri. "I don't stand here and claim to be the conservative alternative to Mitt Romney. I stand here to be the conservative alternative to Barack Obama." Romney enjoyed strong establishment backing in Minnesota, with the vocal support of former governor Tim Pawlenty, yet he trailed not just Santorum but also Rep. Ron Paul (Tex.), finishing a distant third. Addressing supporters in Denver, Romney congratulated Santorum and insisted that he still expects to eventually become the nominee. "We're going to take our message of liberty and prosperity to every corner of the country, and when this primary season is over, we're going to stand united as a party behind our nominee to defeat Barack Obama," Romney said. Paul, who has yet to secure a win in the 2012 sweepstakes, mobilized his loyal support networks in the three states and was banking on low turnout in the nonbinding contests to give him a win. But he finished third in Missouri and was trailing in Colorado. Gingrich did not compete in Missouri and spent limited time in Colorado and Minnesota. He looked past Tuesday's contests and instead campaigned in Ohio, one of several delegate-rich states voting on Super Tuesday.