Allegheny County Executive Dan Onorato will be in Philadelphia today to herald an endorsement from the Pennsylvania Council of Teamsters.

It is the first major labor union endorsement in the race for the Democratic nomination for governor. The announcement was calculated to give the Onorato campaign a sense of momentum heading into a major Democratic Party forum. It comes on the eve of a weekend meeting of the Democratic State Committee in which party officials are expected to consider an endorsement vote among four candidates including Mr. Onorato, Auditor General Jack Wagner, Scranton Mayor Chris Doherty and Montgomery County Commissioner Joe Hoeffel.

Party rules demand a two-thirds supermajority for an endorsement.

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