DENVER – Colorado’s presidential electors must vote for the winner of the state’s popular vote, a federal appeals judge ruled Tuesday in a case filed by three dissident electors who sought to vote for someone other than Hillary Clinton in the 2016 election.

It was a second setback for Polly Baca, Micheal Baca and Robert Nemanich, who objected in an earlier federal lawsuit to a state requirement that they vote for Democrat Clinton. They sued Secretary of State Wayne Williams, arguing that Williams’ enforcement of the law interfered with their performance of a federal function.

Senior U.S. District Judge Wiley Daniel rejected their argument that Colorado’s electoral statute interfered with their free speech rights. The three had accused Williams with voter intimidation because he wouldn’t allow Polly Baca to vote for someone other than the winner of Colorado’s popular vote.

A Denver judge ruled against Polly Baca and Nemanich before the Electoral College ratified Donald Trump’s election in December 2016. That ruling effectively stopped Colorado’s electors from joining a longshot effort to unite with Republicans behind a compromise presidential candidate other than Trump.

The state Supreme Court upheld that ruling. Daniel, who sits on the 10th U.S. Circuit Court of Appeals, previously rejected an emergency appeal, calling it a “political stunt.” The electors subsequently filed a federal lawsuit.

Clinton defeated Trump in Colorado by 5 percent of the vote. The three Colorado electors were part of a group across the country that tried to convince colleagues to vote for someone other than Clinton or Trump and hand the election to a compromise candidate.

Williams removed Micheal Baca, a Bernie Sanders supporter, for trying to vote for Ohio’s Republican governor, John Kasich, at an electors’ meeting at the state Capitol ahead of the Electoral College. A substitute elector voted for Clinton.

Polly Baca and Nemanich ultimately cast their votes for Clinton, as did Colorado’s six other electors.

The Colorado electors faced up to a year in jail and a $1,000 fine if they defied the law and voted for someone other than Clinton. Colorado’s Attorney General, Cynthia Coffman, refused to prosecute Micheal Baca.

“The only thing I asked the electors to do was follow the law,” Williams said when the latest lawsuit was filed.

At the Electoral College, Trump won 306 electors, exceeding the 270 needed to put him in the White House.

Some 28 other states have laws binding their electors to the winner of the popular vote.