Firefighter union head Mahlon Mitchell latest Dem to challenge Wisconsin Gov. Scott Walker

MADISON - Firefighter union head Mahlon Mitchell announced his run for governor Monday, joining a field of Democrats that is beginning to look nearly as crowded as last year's GOP presidential primary.

Mitchell, the president of Professional Fire Fighters of Wisconsin, kicked off his campaign with a spin through Green Bay, Milwaukee and Madison.

It's the second statewide campaign for Mitchell, who lost the 2012 recall race against GOP Lt. Gov. Rebecca Kleefisch.

In a tweet, Mitchell said that a victory next year would give Scott Walker 12 years in office.

"He's already had eight years in office, and he's failed us, the people of Wisconsin!" Mitchell said.

U.S. Rep. Gwen Moore of MIlwaukee immediately threw her support behind Mitchell Monday in a statement addressed to him.

"As I survey the field forming, I am even more impressed with your cognitive and emotional intelligence, your statewide leadership experience, your public policy acumen and service," Moore said in the statement to Mitchell.

State Republican Party spokesman Alec Zimmerman said that Mitchell had already been rejected once by Wisconsin voters during the recall.

“Union boss Mahlon Mitchell went to extreme lengths to protect big government special interests during the recall,” Zimmerman said. “After being rejected by voters before, Mitchell is doubling down on the failed policies of yesterday.”

The opposition of Mitchell and other professional firefighters in the state was notable during the recall because firefighters were exempt from Walker's 2011 repeal of most collective bargaining for public workers, which sparked the recall election. One exception was firefighters in Milwaukee, who have backed Walker.

Mitchell became a frequent speaker at labor protests in those years, taking him from a near unknown to a familiar figure at Democratic rallies.

Republicans have pointed out in the past that Mitchell sent out a press release praising Walker the day that the governor unveiled his union bargaining proposal.

Mitchell has said that he had made the mistake of sending out the release before having fully read Walker's legislation. He ended up reversing himself on the legislation shortly afterward and has opposed Walker's law since them.

A Madison firefighter, Mahlon was born in Milwaukee, grew up in Delavan like Walker, and lives with his wife and two children in Fitchburg.

It won't be easy for groups looking to organize candidate forums and debates in the Democratic primary.

The field of Democrats running for governor now includes state schools Superintendent Tony Evers; Milwaukee businessman Andy Gronik; state Rep. Dana Wachs of Eau Claire; Sen. Kathleen Vinehout of Alma; former state Democratic Party chairman Matthew Flynn; and political activist Mike McCabe.

The Democratic primary could still get more crowded. Other potential candidates include former state Rep. Kelda Helen Roys of Madison and Madison Mayor Paul Soglin.