Is the Denver Sheriff's position not an elected position? What's the difference at that point between the Chief of Police and Sheriff?

http://kdvr.com/2015/10/15/mayor-to-...rsday-morning/

"Mayor Michael Hancock will announce the new Denver sheriff on Thursday morning.The announcement will be made at the City and County Building and comes after a nationwide search was conducted by the independent consulting firm Hillard Heintze. Twenty-five people applied for the job."