Labor groups won a landmark and lopsided victory Tuesday as Missourians voted by referendum to overturn the state’s new right-to-work law, an embarrassing rejection for the state’s Republican lawmakers.

Proposition A asked voters whether or not they would like to enact the right-to-work statute that the state legislature passed and former Gov. Eric Greitens (R) signed early last year. The “no” votes defeated the “yes” by a 2-1 margin, with 937,241 against the proposition and 452,075 for, according to returns released Tuesday night by the secretary of state.

The AFL-CIO union federation called the results “historic.”

“The defeat of this poisonous anti-worker legislation is a victory for all workers across the country,” Richard Trumka, the federation’s president, said in a statement.

The ballot measure drew interest far beyond Missouri due to the rapid spread of right-to-work laws around the country. Such laws give workers who are covered by a union contract the option to not pay any union fees while still enjoying the contract’s protections. Unions are likely to lose members and funding after a state becomes right-to-work.

The Republicans who control both chambers of the legislature thought they made Missouri the 28th right-to-work state last year. But labor groups and their allies succeeded in rounding up enough signatures to put the question directly to voters, then spent months building a “no” campaign to drive voter turnout.

The result was a rare victory for unions in the nationwide right-to-work fight. Although the laws used to be confined mostly to the South and West, the anti-union groups that back them have succeeded in making them the norm rather than the exception around the country. Even longtime labor strongholds like Michigan and Wisconsin have passed right-to-work measures in recent years, thanks to GOP control of state government.

Unions are hoping that Missourians’ decision to reject right-to-work takes some steam out of the nationwide right-wing campaign to expand them. In the runup to the vote, they argued that the referendum would prove that the lawmakers rushing to enact them were out of touch with voters on the issue.

“We think that the legislature and the people are miles apart on this,” Erin Schrimpf, a spokeswoman for the labor-backed coalition We Are Missouri, told HuffPost the night before the vote.

The “no” campaign outspent “yes” groups by an eight-to-one margin ahead of the vote, according to an analysis by the Missouri Times. Labor groups also fanned out with their door-knocking operations, trying to reach not only union members but the general public with their argument that a right-to-work law would drive down wages and working conditions for everyone.