Future of Unions in the Balance.

Two months before Barack Obama is to be sworn in as president, opening salvos are being launched over what could become one of the thorniest issues his administration will face next year.

Organized labor, which spent more than $80 million to put Democrats in the White House and Congress, wants Obama to deliver on its priority: new rules to make it easier to unionize workplaces.

A union-backed organization founded by one of Obama's economic advisors plans to start a national ad campaign today calling for passage of the Employee Free Choice Act. {American Rights at Work}

Obama and his vice president-elect, Joe Biden, embraced the measure in the Senate last year and on the campaign trail this year, particularly in front of union audiences. (The bill passed the House last year, but in the Senate, Republicans succeeded in blocking it because Democrats lacked the 60 votes necessary to cut off debate.)

But if the president-elect pushes for the legislation, he risks alienating business -- which also contributed heavily to his campaign and his party and will be crucial to his efforts to fix the economy and overhaul the healthcare system.