MONTGOMERY, Ala. (AP) — Alabama lawmakers voted Tuesday to withhold economic incentive dollars from companies that voluntarily recognize a union instead of holding a secret ballot election.

The Alabama House of Representatives voted 72-30 for the Senate-passed bill after adding minor amendments. The bill now returns to the Alabama Senate where senators will decide whether to go along with House changes to the bill.

The legislation, which would impact future incentive packages, comes as multiple Southern governors oppose a unionization push directed at auto manufacturers that have been lured to the South with the help of large incentive packages. Georgia Gov. Brian Kemp signed similar legislation on Monday. Tennessee has a similar law in place.

The measure says that companies would be ineligible for economic development incentives if they voluntarily recognize a union after a majority of employees return union-authorization cards — a process sometimes called “card check-off.” A secret ballot election over creating a union would be required for the company to remain eligible for economic incentives.

“It doesn’t stop unions. It just gives the employee the right to vote in private,” Republican Rep. Scott Stadthagen said during debate.

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Opponents argued that the proposal could be in conflict with the National Labor Relations Act, which governs union organizing, and allows companies to voluntarily recognize unions that show support from a majority of employees.

“I think we’re going down a slippery slope by saying that we’re going to dangle this carrot over your head, saying that we’re going to take away any opportunity that you have for economic benefits in this state if you do any of these things,” Democratic Rep. Napoleon Bracy said during debate.

A telephone message to the Alabama AFL-CIO about the bill was not immediately returned.

The Alabama proposal does not affect companies that are already unionized.