Taking its last possible legal shot, the Utah Republican Party on Tuesday asked the U.S. Supreme Court to overturn a popular 2014 state election law that allows candidates to qualify for the ballot through the caucus-convention system and/or by collecting signatures.

The party argues again that the law interferes with its constitutional right of association to select nominees as it chooses — and it prefers to use only the traditional caucus-convention system.

The law, SB54, was a compromise to stop a ballot initiative that seemed poised to scrap the caucus-convention system and replace it with a direct primary. Count My Vote, which pushed the initiative, said the caucus system tends to give extremists in parties extra power and helps nominate people outside the political mainstream.

Count My Vote, whose founders include former Utah Gov. Mike Leavitt, also argued that the caucus-convention system often cuts out most of the electorate in choosing party nominees, giving that power to a relatively small pool of delegates.

In its appeal, the party argues that the court previously ruled that political parties have a First Amendment right “to choose a candidate-selection process that will in its view produce the nominee who best represents its political platform.”

However, the 10th Circuit Court of Appeals upheld SB54 earlier this year in a 2-1 decision by saying “states must have flexibility to enact reasonable, common-sense regulations designed to provide order and legitimacy to the electoral process.”

The appeals court denied a subsequent request to have the case reconsidered by the full court instead of just the panel of three judges.

SB54 has split the Utah Republican Party. Business groups and moderates applaud the new law, and many of them quit donating to the party when they feared their money would go to the lawsuit.

Right-wing leaders, who dominate the party’s central committee, like the convention system that helped give them power, and they have pushed the legal challenges.

When Party Chairman Rob Anderson tried to stop the lawsuits by saying the costs were bankrupting the party, the central committee stripped him of such powers and created a Constitutional Defense Committee to make decisions on the appeal.

The party had once amassed a $410,000 debt in pursuing the case. But earlier this year, Dave Bateman, CEO of Entrata software, stepped in and “acquired the debt” from party lawyers — who settled for about 40 cents on the dollar — with some strings attached.

Bateman said he paid the lawyers $175,000 to settle their bills and agreed to cover future costs of continuing legal battles against SB54. The catch is, the party would need to repay him if it ever dropped the lawsuit without his permission or before all appeals were exhausted — including the final appeal to the U.S. Supreme Court.

Bateman, in an earlier interview with The Tribune, said he saw the appeals court defeat as an opportunity in taking the case all the way to the high court.

“If we do win it now, it will set precedent not just in the 10th Circuit but all across the United States,” Bateman said. “It’s a huge opportunity to make an impact on a national level to assert the rights that parties have to nominate candidates that they think best.”

Count My Vote attempted another ballot initiative this year to help cement SB54 into law. It appeared to have enough signatures to qualify for the ballot, but an effort funded by Bateman thwarted that by persuading enough people to withdraw their signatures.