Democrats’ chances of winning back control of the House of Representatives in 2024 just got a big boost from the most unlikely of places: the conservative-dominated Supreme Court.

The court’s 5-4 decision Thursday morning in Allen v. Milligan found that Alabama’s Republican-controlled legislature had diluted Black voting power by drawing only a single majority-Black congressional district (out of seven statewide seats) after the 2020 census. The ruling will lead to the creation of an additional majority-Black congressional district in the state — eliminating a Republican-held seat and likely giving Democrats an additional seat in the House of Representatives, where Republicans currently hold a 222-213 edge.

The decision is a surprise victory for the Voting Rights Act, which was used to bring the challenge to the Supreme Court despite being repeatedly gutted by the high court. It could also provide a roadmap for additional challenges to racially gerrymandered congressional maps across the South, including in Louisiana, which similarly has only one majority-Black congressional district out of six seats, despite Black voters making up a third of the Louisiana electorate, and in South Carolina, where a separate challenge to Republican redistricting efforts will be heard by the Supreme Court.

Those redistricting challenges could create additional minority-majority districts that would likely favor Democrats, meaning a raw gain for Democrats in the House of anywhere from two to four new congressional seats, according to some elections analysts. Additional court decisions in places where redistricting is being contested, like Georgia and Texas, could add to that seat gain — and help erase the current Republican margin in the U.S. House.