(CNN) Missouri voters handed the state's unions and the labor movement nationwide a win Tuesday evening, opting to reject the state's right-to-work law.

Tuesday's referendum in the state gave voters the chance to strike down a law the state Legislature passed last year that would prohibit employees from being forced to join a union or to otherwise pay "fair share" fees to a given workplace's union. Rules like this are commonly referred to as "right-to-work" laws, and by prohibiting requirements for employees to join a union or pay fees to a union negotiating on their behalf, they are generally understood to weaken labor organizations in places where they are enacted.

The Missouri vote marked a major victory for unions in an era replete with bad signs for organized labor. Union membership levels have declined for decades, and the ascendance of anti-union politicians across the country has handed unions legislative defeat after legislative defeat.

President Donald Trump's election solidified the trend on the national level, with Trump making his mark on the National Labor Relations Board and appointing a slew of pro-business judges to federal courts. And the Supreme Court, in one of the most watched cases from its recent term, overturned a ruling from the 1970s that required public employees who received the benefits of unions to pay dues for nonpolitical work of the unions -- a potentially major blow to public sector unions.

The AFL-CIO and other major labor groups had set their hopes and considerable resources on the effort to overturn Missouri's law by winning a "no" vote for Proposition A.

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