DENVER (AP) – A leading candidate in the crowded Colorado Senate Democratic primary is ending his campaign. Former state Sen. Mike Johnston becomes the first casualty of former Colorado Gov. John Hickenlooper’s late entry into the race. Hickenlooper last month dropped his presidential bid and instead announced he wanted to challenge Republican Sen. Cory Gardner. In a statement Tuesday, Johnston said he realizes now that winning the primary would require “an expensive and negative campaign.”
