The Maine Supreme Court ruled unanimously Monday that an expansion of ranked choice voting would violate the state constitution.

The court was considering a Democratic bill to expand ranked choice voting to races for governor and the Maine legislature.

Ranked choice voting is already used in primaries and federal races in Maine, but the state constitution requires a plurality to win general elections for state offices.

Maine GOP Chair Jim Deyermond praised the ruling, saying that it “provides clarity against efforts to pollute our state elections with Ranked-Choice Voting.”

Ranked choice gives voters the ability to select a second and third choice if their preferred candidate doesn’t win.

Democrats and other supporters of ranked choice voting say it helps avoid spoiler candidates that split the vote.