Sen. Joe Manchin, D-W.Va., will co-sponsor the Senate version of House Democrats' PRO Act, which would negate state right-to-work laws and force some workers to pay union dues in order to keep their jobs.
"I look forward to working with my colleagues, on both sides of the aisle, to move this bill through a legislative process," Manchin said on Monday, Politico's Corbin Hiar reported.
Manchin was speaking at a National Press Club event with United Mine Workers of America head Cecil E. Roberts Jr.
West Virginia passed right-to-work legislation in 2016, according to the National Right to Work Legal Defense Foundation. Roughly 10% of West Virginia workers are union members, according to data from the Bureau of Labor Statistics.
Manchin's support of the PRO Act was not guaranteed since he often breaks with his party. Still, the bill is not expected to be able to overcome a filibuster in the Senate.
The Coalition for a Democratic Workplace, which represents groups including the U.S. Chamber of Commerce and National Restaurant Association, criticized Manchin.
"It is very disappointing that Senator Manchin has chosen to side with union bosses over West Virginia’s workers and small businesses, especially during a time of economic turmoil," CDW Chair Kristen Swearingen said in a statement.
"We hope Manchin will reconsider co-sponsoring this legislation as his legacy of bipartisanship will be irrevocably tainted if he supports anti-worker legislation that invades employees’ privacy and will kill West Virginia jobs, while taking the hard-earned income away from small businesses and employees to boost the coffers of organized labor."
Advocates of the measure say it would bolster collective bargaining rights. AFL-CIO President Richard Trumka told NPR last month the bill would be a "game changer."
"If you really want to correct inequality in this country – wages and wealth inequality, opportunity and inequality of power – passing the PRO Act is absolutely essential to doing that," Trumka said.
Meanwhile, South Carolina Attorney General Alan Wilson is leading a coalition of state attorneys general in opposition to the bill.
"Our nation has always been one of opportunity that rewards individual choice, ingenuity, and initiative," Wilson said in a letter. "Our laws have long preserved the ability of employees to speak for themselves, to make informed decisions, and to work without being forced to pay fees to third parties."
Fox News' Bradford Betz contributed to this report.