The head of the state firefighters’ union is the latest Democrat to run against Governor Scott Walker next fall. Mahlon Mitchell of Fitchburg announced his bid this (Monday) morning, telling the Wisconsin State Journal it’s “time for a change” after eight years of the Republican Walker. Mitchell ran for lieutenant governor in the 2012 recall elections, when he lost to Republican Rebecca Kleefisch. Mitchell, a Delavan native, became the first African American president of the Professional Fire Fighters of Wisconsin in 2011. He joins a crowded field of Democratic gubernatorial candidates that includes state public school Superintendent Tony Evers, former state party chairman Matt Flynn, and state lawmakers Kathleen Vinehout and Dana Wachs.