Former Rep. Dave Obey (D-Wis.) endorsed Milwaukee Mayor Tom Barrett (D) in Wisconsin's gubernatorial recall race on Monday morning, saying he believed he was "by far the strongest candidate" to defeat Gov. Scott Walker (R).

So far, the Democratic primary has been dominated by Barrett and former Dane County executive Kathleen Falk, the other frontrunner, who are trying to prove their pro-labor credentials.

Falk has the backing of at least six unions, including the American Federation of State, County and Municipal Employees (AFSCME) and the Wisconsin Education Association Council (WEAC). EMILY's List, the Sierra Club and Young Progressives of Wisconsin also endorsed her.

In a Monday conference call, Obey assured reporters that Barrett was committed to restoring the collective bargaining rights for public workers that Walker took away last year.

"I've spent 42 years in public life, fighting for a square deal for working people," Obey said in the conference call. "And I've walked many a picket line with workers and teachers. I firmly believe that bargaining rights for workers must be restored. ... Tom has the personal qualities that are needed to cleanse the poisonous atmosphere that has dominated Wisconsin for the last year. He will be a strong governor, and a fair governor; he will be a rubber stamp to nobody. But he will be a strong ally of working people from Kenosha to Superior and all points in between."

On Sunday, AFSCME apologized for circulating a video purportedly showing Barrett supporting Walker's anti-union policies. It acknowledged the video was "over the top" after receiving criticism even from another union in the state.

Obey criticized AFSCME, saying the video was "outrageous."

"In suggesting that Tom somehow supported Scott Walker in his assault on collective bargaining, I think is just incredibly off the wall and unfair," he said on Monday. "And that's why I'm pleased that it appears that a good amount of objection from the union rank and file has pushed them to put out a statement apologizing."

Falk has promised to veto any budget from the legislature that does not include a reinstatement of workers' collective bargaining rights in the state.

Barrett -- who has tussled with unions during his time as mayor -- has not made the same pledge, upsetting some labor officials. He told The Huffington Post recently that while he will "certainly fight and be successful in restoring collective bargaining rights," he does not want to commit to one strategy and limit his flexibility.

There are currently four Democratic candidates competing in the May primary. Barrett and Falk are considered the two frontrunners, with state Sen. Kathleen Vinehout (D-Alma) and Secretary of State Doug La Follette also in the race.

Obey unofficially expressed his support for Barrett long before the mayor even announced that he was running. In January, when Falk was the only Democrat who had officially jumped in, Obey told The Huffington Post that he still wanted to see either Barrett or Sen. Herb Kohl (D-Wis.) declare their candidacy. He said he was actively encouraging one of them to do so.

The primary is set for May 8, and the general election will be on June 5.

More here on the state of the Democratic primary in the recall.

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