DENVER (AP) – Two Colorado electors are appealing a judge’s ruling that they must vote for the presidential candidate who won their state’s popular vote.

The electors filed an appeal with the 10th Circuit Court of Appeals in Denver after a federal judge Monday ruled they had to follow Colorado law and vote for the winner of the presidential election in the state.

Hillary Clinton won Colorado and the two electors are Democrats but want to vote for a Republican in a longshot effort to convince other Republican electors to abandon Donald Trump.

That would prevent Trump from becoming president.

But it’s highly unlikely to succeed. Trump won 306 electors last month, more than enough to put him in the White House. Only one Republican elector has said he won’t vote for Trump.