Labor leaders are giving President Barack Obama a pass — for now — on his failure to put “card check— legislation at the top of his to-do list, but they are preparing to demand immediate action if Democrat Al Franken is seated as Minnesota’s Senator.

“President Obama made it very clear he supports— the Employee Free Choice Act, one labor official said. “We take him at his word.—

Obama’s path to victory — not to mention Democrats’ 2006 takeover of Congress — was paved with labor’s support. The unions, in turn, have no greater priority for the president and Congressional Democrats than EFCA, which would provide a boon to labor by making it easier for workers to unionize.

But Obama, since becoming president, has made little mention of legislation that causes fits up and down K Street, where business operatives are waging an unrestrained war to kill it.

Beaming in comments via video from Washington, D.C., to the AFL-CIO meeting in Miami early last month, Obama mentioned the legislation almost in passing at the end of his remarks.

“As we confront this crisis and work to provide health care to every American, rebuild our nation’s infrastructure, move toward a clean energy economy and pass the Employee Free Choice Act, I want you to know that you will always have a seat at the table,— he said.

Asked about Obama’s position on the bill last week, White House Press Secretary Robert Gibbs was unusually terse. “He continues to support the legislation,— Gibbs said.

White House officials maintained their low-key approach when prodded Wednesday on the issue, declining to say anything other than that Obama continues to back the measure.

Some union officials believe Franken’s victory in the contested election against former Sen. Norm Coleman (R-Minn.) is all but certain in the wake of a court decision Tuesday favoring Franken. But the outcome may be far from final, and Republicans are continuing to back Coleman. Legal wrangling could continue for some time.

Even if Franken gets in, supporters of the legislation will remain one very difficult vote short of the 60 that they need to move the legislation to the floor. Labor guardedly expects unified backing of Democrats on the procedural motions requiring 60 votes. But that only gets them to 59.

The great union hope for No. 60, Sen. Arlen Specter (R-Pa.), decided last month that he was against the measure, and union officials acknowledge the road to finding another GOP vote is a steep one. But they nevertheless believe they have a commitment from Obama to lead them to the mountaintop.

“We have been assured that at the appropriate time, once Franken is seated, they are looking to be very aggressive,— one labor official said. “They are going to move into a different mode on this.—

Obama will then be asked to become personally involved in the legislative effort, along with his senior aides.

Union officials want the president to try his hand with Republicans, particularly Specter and Sens. Susan Collins and Olympia Snowe. The two moderate Republicans from Maine, viewed as having decent relations with the White House, are seen by labor as among the best shots at the pickup that they desperately need. But they may be long shots.

“I think card check is dead,— one respected Democratic lobbyist said. “There will be no 60th vote unless they change some of the substance of it.—

But labor officials plan to try to win with the bill that they have now, launching a two-week recess grass-roots drive that will target Senators like Specter, Collins and Snowe, as well as some Democrats whom union officials feel need a refresher course in labor activism in order to stay with the bill.

With business officials certain to be blanketing the Hill, Obama’s job will be to keep Democrats in line when the lobbying begins.

White House support for the measure becomes even more critical with the likelihood that Democratic House leaders will not put the measure to a vote until they see how it plays in the Senate.

“A lot of House Members do not want to vote on this if it’s not going to happen,— another top Democratic lobbyist said. “If you’re from a moderate or a conservative district, you’ll vote for it if it comes up, but you’re not eager to do it.—

Backers hope Obama can provide the lift that a strong House victory might have given the legislation.