"The protest candidates will run as Democrats to guarantee that there is one clear date for the primary election and one clear date for the general election," said Stephan Thompson, RPW's executive director.

Barrett said in an email to supporters Friday that he would fight to restore collective bargaining rights "because it's the right thing to do, and it's necessary to heal Wisconsin."

Barrett said the state needs a governor who is focused on jobs, not ideology, and who is committed to bring the state together to heal political wounds.

Republican Party spokesman Ben Sparks said voters have no interest in electing Barrett, who has twice lost in runs for governor. He was defeated in the 2002 Democratic primary by former Gov. Jim Doyle.

Walker campaign spokeswoman Ciara Matthews said they have been expecting the recall election to go forward, but believe Wisconsin voters will back the governor's record.

"Now it is time for voters to examine the choice they will be faced with in June," Matthews said.

Walker will be only the third governor in U.S. history to face a recall, joining California Gov. Gray Davis, who was recalled in 2003, and North Dakota Gov. Lynn Frazier, recalled in 1921.