Despite faltering support for a bill that would make it easier for unions to organize, backers of the Employee Free Choice Act are continuing to push key Senators to move forward on the legislation.

After a two-week recess during which big business and unions blanketed lawmakers’ districts with anti- and pro-“card check— rallies, advertisements and phone calls, both sides are soldiering on in what has become a multiyear, multimillion-dollar lobbying campaign.

Although there have been rumblings among labor organizers, including Service Employees International Union President Andrew Stern, that unions may be open to a compromise, pro-EFCA groups showed no mercy on Capitol Hill this week.

“We’re coming off the recess, where we’ve made the biggest grass-roots effort around a legislative issue that we’ve made in recent memory,— said Bill Samuel, head of AFL-CIO’s government affairs operation.

Union organizers held more than 400 grass-roots events, sent more than 27,000 letters to Members of Congress and put in nearly 100,000 calls supporting EFCA. Additionally, the unions spent more than $1 million on two TV ads over the recess, AFL-CIO spokeswoman Amaya Smith said.

Samuel downplayed any talk of modifying EFCA to make it more palatable for business.

“I don’t think the question is Are we open to compromise?’— Samuel said. “The way Congress works, a bill is marked up, amendments are offered, it’s either improved or weakened, and you make a judgment at that time.

Stern “is firm about the principles and of getting labor law passed in this Congress, and we are too,— he added, referring to Stern’s comments to the Washington Post editorial board, in which the SEIU president noted that “no matter what you do, you have to change the election process.—

SEIU spokeswoman Christy Setzer echoed Samuel’s call of dedication to passing the EFCA.

“Given our current economic crisis, now more than ever, we remain committed to the principles of the Employee Free Choice Act: allowing workers, not employers, to choose how and when to form a union; enforcing real penalties for employers who break the law; and ensuring that those who’ve chosen a union can actually secure a contract,— Setzer said in a statement.

Keeping that message in mind, labor organizers are continuing to put pressure on lawmakers.

Jobs with Justice, a national campaign for workers’ rights, kicked off union actions Wednesday with a press conference moderated by Barbara Ehrenreich, author of “Nickel and Dimed.—

EFCA supporter Sen. Sherrod Brown (D-Ohio) also attended, rallying attendees to continue to press the Senate to pass the card check bill.

Brown, whose daughter works as an organizer at the SEIU, told union leaders that the opposition to the bill is largely the same business types that have historically opposed Medicare, Social Security and the minimum wage.

Ricardo Valadez of Jobs with Justice agreed with Brown.

“We’ve been fighting for reform for labor legislation for years,— Valadez said. “It will be hard, but there are a lot of different ways to get to 60 votes.—

The group had representatives from Colorado, Pennsylvania, Indiana, Virginia, Maine and Missouri on Capitol Hill meeting with Sen. Susan Collins (R-Maine) and aides from the offices of Sens. Jim Webb (D-Va.), Claire McCaskill (D-Mo.) and Bob Bennett (D-Colo.).

The community leaders also delivered packets that included a letter with 570 Workers’ Rights Board member signatures, more than 300 endorsements from local community groups and more than 22,000 postcards from nonunion allies.

Business groups are also continuing to put pressure on Members to oppose the bill.

A coalition of minority business leaders — including the Asian American Hotel Owners Association; the National Association of Black Hotel Owners, Operators & Developers; the National Black Chamber of Commerce; the Latino Coalition; and the U.S. Hispanic Chamber of Commerce — held their own press conference Tuesday to continue lobbying against the card check bill.

“They want to come in and run your business for you and probably run it into the ground,— National Black Chamber of Commerce President Harry Alford said.

Additionally, the U.S. Chamber of Commerce continued its efforts, starting a $1 million ad buy last week in Nebraska, Colorado, Virginia, Louisiana and North Dakota. The ads, which will continue through next week, feature home-state residents urging people to tell Congress that there is no compromise.

The U.S. Chamber of Commerce also helped the Arkansas State Chamber of Commerce with a fly-in of about 100 people who met with Arkansas Democratic Sens. Blanche Lincoln and Mark Pryor.

The Associated Builders & Contractors also turned up the heat Tuesday, sending a letter detailing the group’s initiatives over the recess with the names of more than 3,000 contractors and more than 200 electrical engineers.

“There is no room to compromise on this legislation,— said Brewster Bevis, director of legislative affairs for the group. “I think those guys see their baby is dying a slow death, and they are looking for anything to resuscitate it in any form or fashion.—

The ABC, which has its legislative conference in June, will have about 600 contractors on Capitol Hill with card check as its No. 1 priority.

“I think there’s a very real possibility that we can stop this,— Bevis said. “We’re turning on the after burners, and we’re going to continue on with this fight until we’ve driven the final nail in the coffin.—