By Matt Volz Associated Press

HELENA (AP) – The U.S. Supreme Court on March 23 rejected a Republican Party appeal seeking to close Montana’s primary elections in June, meaning any registered voter will be able to select a GOP ballot.

The Montana Republican Party and eight central county central committees want to require primary voters to register as Republicans before being allowed to participate in the June 7 elections. Two lower courts had denied their request for an emergency injunction, resulting in the long-shot appeal to the nation’s high court.

The court takes up very few petitions it receives, but in this case, Justice Anthony Kennedy had requested more information about the issue. That had given GOP attorney Matthew Monforton a glimmer of hope that the court would intervene, but it denied the appeal without comment a day after all the arguments had been filed.

“We’re going to just continue on and seek relief with regard to crossover voting in the 2018 primaries,” Monforton said.

The Republican plaintiffs’ lawsuit, which is still pending in a lower court, argues the system violates their First Amendment right to associate. They contend the state’s open-primary system allows Democratic, independent or third-party voters to affect the outcome of their elections and Republican candidates must alter their message to appeal to those crossover voters.

Senate Majority Leader Matthew Rosendale and House Majority Leader Keith Regier testified last year that a closed-primary system would help conservative Republicans keep party moderates out of the Legislature.

Attorneys for the state have argued that the Republican plaintiffs have failed to provide evidence of their claims of crossover voting and the century-old primary system should not be changed based on the party’s assumptions that it happens.

Only in very rare circumstances has an election’s outcome been changed by voters aligned with another party deliberately trying to affect it, Secretary of State Linda McCulloch said.

“I think it’s a myth,” McCulloch, a Democrat, said of crossover voting. “I think it’s really a matter of independent voters sometimes voting Republican, sometimes for Democrats.”

Changing the system so close to the elections would have been problematic, she added. It would require many months to properly contact all 635,000 voters in the state about the change, she said.

U.S. District Judge Brian Morris initially ruled against the Republicans in December, saying they have too many unproven claims about crossover voting to issue an injunction but allowed the case to proceed to trial. The 9th U.S. Circuit Court of Appeals was next to reject the request for an injunction, saying the Republican plaintiffs had not shown their case is likely to succeed or that they would be irreparably harmed if the primaries remained open.