Republicans in Congress plan to introduce legislation Wednesday that would prohibit workers nationwide from being forced to support a union.

The national right-to-work legislation likely would be a major blow to organized labor because it would allow millions of workers to opt out of union membership for the first time.

Reps. Joe Wilson of South Carolina and Steve King of Iowa are sponsoring the legislation, which would amend the National Labor Relations Act and the Railway Labor Act to prohibit what unions call "security clauses." These are provisions that permit union-management contracts that require all employees to join a union or pay one a regular fee as a condition of employment.

"At least 80 percent of Americans are opposed to forcing employees to pay dues as a condition of their employment, and our bill would protect workers by eliminating the forced-dues clauses in federal statute. Right-to-work states, like South Carolina, have seen first-hand that job creation and economic growth comes from expanded freedoms. We need to expand common-sense reforms, like those in the National Right to Work Act to protect American workers and create jobs," Wilson told the Washington Examiner.

Twenty-eight states have passed right-to-work laws, which is allowed under the National Labor Relations Act. The most recent to have adopted them are Wisconsin, Kentucky and West Virginia. Missouri is expected to adopt the legislation this month.

Union leaders hate the laws, which are associated with declining membership and depleted treasuries as workers take advantage of the opportunity to opt out of membership. They argue that security clauses are fair because union collective bargaining benefits all workers. Critics counter that belonging to a union should be the individual worker's decision and that economies benefit from giving those workers more freedom.

Republicans have pushed similar right-to-work legislation in previous Congresses, and Wilson and King introduced a version in 2015. But t efforts typically gained little traction.

Right-to-work fans have reason to be more optimistic this time, as President Trump endorsed right-to-work laws during the campaign.