The 9th annual Kaiser Permanente Colfax Marathon takes place on Sunday, May 18, 2014. Register online at www.runcolfax.org. Denver's springtime running event includes seven races: Marathon, Half Marathon, Urban 10 Miler, Bellco Colfax 5K and three divisions of the Marathon Relay: Open, Corporate Cup and Government Cup. The Colfax Marathon Charity Partners Program is one of the largest in the country, with 122 nonprofits raising money and awareness in 2013. With support from the Colfax Marathon, nonprofits recruit runners, build a fundraising campaign and keep 100% of the funds raised.