The endorsing body of the Minnesota AFL-CIO, a labor federation of unions with more than 300,000 Minnesota members, will meet Wednesday to screen gubernatorial candidates. The Committee on Political Education may pick a favorite that same day.

DFL candidates Margaret Anderson Kelliher and Mark Dayton as well as Independence Party's Tom Horner will all meet with the committee, said union spokesman Chris Shields. DFLer Matt Entenza returned the AFL-CIO's questionnaire but is passing on screening, Shields said.

The upcoming meeting may set off some interesting union politics. Kelliher has the backing of the largest member union -- Education Minnesota -- and the third largest union -- the Minnesota Nurses Association and has been announcing more union backing nearly every week since landing the DFL-endorsement. Dayton has the support of AFSCME Council 5, the second largest union, the steelworkers union and a handful of other smaller labor organizations.

It will take a two-thirds vote of the committee, which is made up of representatives from member unions in rough proportion to their strength in the AFL-CIO, to back a candidate. The committee includes almost 70 members and includes Tom Dooher, president of Education Minnesota, and Eliot Seide, executive director of AFSCME council 5.

The committee could opt not to endorse Wednesday.

Although any member union is free to back the non-AFL-CIO candidate, an AFL-CIO nod would bring a massive coordinated effort on behalf of the favored candidate.