Republican Donald Rosier, a Jefferson County commissioner since 2010, has announced his candidacy for the U.S. Senate, hoping to challenge Democratic Sen. Michael Bennet next year.
Rosier formally announced his run Thursday at an event in Arvada. The Denver Post first reported his candidacy.
Already in the GOP race are state Sen. Tim Neville of Littleton, El Paso County Commissioner Darryl Glenn, former Aurora City Councilman Ryan Frazier and former Parker Mayor Greg Lopez.
Bennet is seeking a second term in this battleground state. In 2010, he narrowly edged Republican Ken Buck, who went on to win an open U.S. House race last year.
