A Colorado representative to the Electoral College is helping lead a movement to block Donald Trump from taking the White House.

Micheal Baca, a Denver Democrat and member of the state’s Electoral College delegation, is working to persuade Republican electors in other states to support a different candidate.

And he has the blessing of Colorado Democratic Party Chairman Rick Palacio.

“I think the majority of the voters in this country are very upset at the outcome of this election,” Palacio said in an interview. “The electoral college didn’t do a majority of the American people a favor in this election and I think there are many who are trying to figure out ways to prevent Trump from taking office. I applaud Micheal for doing his part.”

Baca and colleague Bret Chiafolo, a Washington state elector, created what they call “Moral Electors.” If 37 Republican electors vote against Trump, it would prevent the Republican from winning the presidency and could put the question to the House of Representatives.

Although he’s a Democrat, Baca says he’s willing to support a Republican candidate to block Trump. He then hopes the Republican president would pick a Democratic vice president.

“This is not about Hillary,” he said. “This is about trying to stop Donald Trump.”

The House has been forced to decide the presidency in the past, but never in this manner. When the Electoral College is deadlocked, the House is supposed to choose from among the top three electoral vote-getters. But since no third-party candidate won a state, only Trump and Democrat Hillary Clinton stand to receive electoral votes.

So, for the election to be decided in the House, electors would have to write in a third candidate: say, Libertarian Gary Johnson or Evan McMullin, the conservative from Utah. They could even write in someone who wasn’t running, such as Ohio Gov. John Kasich or former Massachusetts Gov. Mitt Romney.

“Yes. It’s possible,” said Kyle Saunders, a political science professor at Colorado State University. “Is it likely? No.”

To win the presidency, a candidate needs 270 out of 538 available Electoral College votes, which are divvied up among the states and Washington, D.C., based on population. But the electoral votes aren’t automatically given to a state’s winning candidate. Electors have to cast a vote at their state’s meeting of electors, which will occur Dec. 19.

Procedures for appointing an elector vary from state to state, but it’s typically done at the party convention or by a party committee.

There’s no federal law requiring electors to vote for the party that nominated them, but 29 states and Washington, D.C., have laws that attempt to force presidential electors to vote with the will of their state’s voters, according to the National Conference of State Legislatures.

Some states impose fines. Others, like Colorado, don’t allow for so-called “faithless electors.” If an elector does not cast a vote for the right candidate, they are removed and replaced with a new elector, according to the Colorado secretary of state’s office. So Baca is required under Colorado law to cast his vote for Clinton because she won the state’s nine electoral votes.

Twenty-one states don’t have any law directing their electors how to vote. And in some of those that do, an electoral voter could still get away with it by paying a fine.

“It opens up a whole constitutional can of worms. This has only been tried a few times and really, it’s been a while,” Saunders said. “It’s absolutely futile.”

For one thing, even if renegade electors could force an Electoral College deadlock, to defeat Trump would require a Republican-majority House to vote against its own presidential nominee. That would risk the ire of the millions who voted for him, and only fuel Trump’s prior warnings of a “rigged” election.

“I think that feeds right into that,” said Michael Berry, an associate professor of political science at the University of Colorado Denver. “Because it’s unlikely to be successful, I just don’t think it’s a wise political move.”

Forcing an Electoral College stalemate like this would be unprecedented, Saunders said. The last time the House decided an election after a deadlocked Electoral College was 1824, but that year, four candidates won states.

No elector has even crossed party lines since 1972, when a Republican elector cast a ballot for the Libertarian ticket, according to the NCSL. More recently in 2004, a Minnesota elector nominated by the Democratic Party voted for John Edwards, the running mate of Democrat John Kerry.

Baca says he’s aware that the chances of success in blocking Trump are slim. “This is a longshot; it’s a pipe dream,” he said.

A 24-year-old graduate student at Northern Arizona University, Baca is a Marine Corps veteran who now drives for the ride-sharing services Lyft and Uber.

Even before this latest effort, Baca considered voting against Clinton when the Electoral College meets Dec. 19. He is a supporter of Bernie Sanders.

Baca, who became involved in politics for the first time this campaign, believes the popular vote should control who wins the White House. He hopes this effort raises awareness of the problems with the Electoral College. And he’s upset about Trump’s position on climate change.

“We cannot just rip up the Paris climate accord,” Baca said. “We cannot have a climate denialist (in the White House).”

If electors vote with their states, Trump would secure as many 306 electoral votes. He has enough states for 290 today and is leading in Michigan, which has not made its results official and has 16 electoral votes.

Updated at Nov. 16, 2016 at 10:30 a.m.: This story was updated to reflect that in 2004, a Minnesota elector nominated by the Democratic Party voted for John Edwards, the running mate of Democrat John Kerry. An earlier version had the wrong year.