Updated at: 03/02/2014 9:57 PM
(AP) DENVER - DENVER (AP) â€” Republican Rep. Cory Gardner formally kicked off his Senate campaign on Saturday by tying his challenge to Democratic Sen. Mark Udall to the GOP's efforts to reverse its decade-long slide in this key political bellwether state.
"In 2008, Colorado led the nation in change," Gardner said, alluding to the election of Udall and the nomination of Barack Obama for president during the Democratic National Convention in Denver. "In 2014, we can change it again."
Gardner, 39, represents his party's best shot at breaking a 10-year drought in topline races here. Republicans have not won a single presidential, U.S. Senate or gubernatorial election in Colorado since 2004 because of their trouble appealing to women, young people and Hispanics -- factors that have hobbled the GOP nationwide.
In an indication of the Republican enthusiasm around Gardner, he spoke to a crowd of more than 100 supporters who had braved white-out conditions and subzero temperatures. He was joined on the stage by Weld County District Attorney Ken Buck and state Rep. Amy Stephens, both of whom had been competing for the GOP nomination to challenge Udall until Gardner entered the race last week, leading them to drop out and endorse him. State Sen. Owen J. Hill remains in the race.
Buck narrowly lost to Democratic Sen Michael Bennet in 2010, and many Republicans feared he was too gaffe-prone to beat Udall. "Cory is more disciplined than I am, let's be honest," Buck said in an interview. He is now competing for Gardner's congressional seat.
Gardner slammed Udall for voting to approve Obama's health-care overhaul, raise taxes and "infringe Second Amendment Rights." He said he will run on economic development, responsible energy production, a clean environment and education.
Udall's campaign wasted no time in firing back, noting in a statement that National Journal ranked Gardner the 10th most conservative member of the House of Representatives last year.
"Congressman Gardner will be held to account for the out-of-touch votes he cast in Congress," Udall campaign manager Adam Dunstone said in the statement.
Gardner had declined to challenge Udall last year.
In an interview, he said he began to rethink that after his family's health insurance plan was cancelled in October because of the Affordable Care Act. "Democrats called us liars," he said. "We started taking another look" at the race.
Republicans were jubilant about Gardner's change of heart. "Cory's our hope," said Maria Weese, 57. "He makes me smile because I know the future is here."
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