Politico‘s Ben Smith tonight reports that Andy Stern, President of Service Employees International Union (SEIU), one of the most powerful labor leaders and political figures in America, is resigning:

The President of an SEIU local based in Seattle, Diane Sosne, broke the news to her staffers at 11:35 this morning, local time.

"Last night I received confirmation that Andy Stern is resigning as President of SEIU. He has not yet made a public announcement; we will share the details as we become aware of them," Sosne wrote in an email obtained by POLITICO.

Sosne offered no explanation for the move, but another SEIU official speculated that Stern had finally tired of the draining job.

"Health care getting done is a good culmination," the official said.

Stern’s SEIU and President Obama have a longstanding political relationship, and it was widely reported late in 2009 that Stern was the most frequent visitor to the White House during the President’s first year in office.  Stern drove hard behind the recent health care reform act and the push to hold legislators accountable for their positions on the Employee Free Choice Act.  Speculation will swirl until Mr. Stern himself addresses his departure from the most politically connected labor union in the U.S.  [UPDATE: HuffPo's Sam Stein tweets: "SEIU spokesperson Michelle Ringuette: ".Stern will address these rumors at the close of the SEIU Executive Committee meeting this week."]  But without a doubt, what he does next will likely be as significant to the American labor movement as what he has done to date.

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