Paul Ryan held a campaign rally in the gym of Lakewood High School, which the campaign estimates holds about 2,000 people.
Hundreds of people gathered in the gymnasium at Lakewood High School on Tuesday to listen to Wisconsin congressman Paul Ryan.
He told a crowd about his memories of hiking, skiing and fishing in Colorado on vacations.
Romney is spending the day campaigning in Ohio, another key swing state.
Romney publicly praised his running mate's work as necessary to protect the long-term survival of Medicare, the government-run health insurance program for the elderly.
Ryan also held a fundraiser during his trip to Colorado.
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This stop is in Jefferson County, which is considered a swing county in the swing state.
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Next, he'll court voters and donors in Nevada.
(KUSA-TV © 2012 Multimedia Holdings Corporation with The Associated Press)