The 1.4 million-member Teamsters union will endorse Sen. Barack Obama's presidential candidacy today, Democrats briefed on the decision said.

A Teamsters official confirmed the endorsement.

Nothing says tough, or evokes "gruff," more than the Teamsters.

Obama and Hillary Clinton have been courting the union and its colorful bull of a president, James Hoffa for more than a year. Among labor unions in the United States, the Teamsters are third in size to the Service Employees, who endorsed Obama last week and the National Education Association, which is neutral.

The Teamsters have a storied, occasionally controversial history and are capable of putting large numbers of boots on the ground for their preferred candidates.

The Teamsters were waiting until after Wisconsin's primary before announcing its choice. After briefly flirting with Pres. George W. Bush, the union returned into the Democratic fold when it became clear that Bush and the White House intended to use exploit the PR benefits from the union's outreach without supporting any of their key initiatives.

"I am not in a position to confirm anything at this point," an Obama spokesman said this morning.

Note: in 1998, the Clintons supported former Teamsters Pres. Ron Carey in his failing re-election bid; he lost to Mr. Hoffa, who has since insisted that he has reconciled with the Clintons.

Other large unions remaining neutral, so far, are the United Auto Workers and the Communications Workers of America.

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