Published: March 12, 2010

Greg Sargent reports that Rep. Mike McMahon (D., N.Y.), who voted against Obamacare on its first trip through the House, is being told in no uncertain terms that unions will back a primary challenge if he repeats the trick:

Dem Rep Mike McMahon of New York met yesterday with a top SEIU official and told him he’s likely to vote No, the official tells me. The official: Mike Fishman, president of SEIU 32bj, the largest property workers union in the country, with 120,000 members in eight states.

Fishman told McMahon that the union would not support him if he voted No — and suggested the hunt for a primary or third-party challenger would follow.

“He let us know he’s not supportive of the health care plan,” Fishman says. “We’ve let him know that we can’t support somebody who doesn’t support it.”

“We are going to begin talking to other unions about finding someone else for that seat,” Fishman continued.

The SEIU leader later says, “This is the most important issue on everyone’s plate. We’re sending a message to Democrats: If you can’t support this, we can’t support you.”