A federal judge on Thursday denied an attempt to cancel at-large Nevada caucus sites, boosting Barack Obama's campaign, which has the backing of Las Vegas' largest labor union.

Judge James Mahan washed his hands of the case, saying that existing election law allows for the Democratic Party to resolve the differences internally and it's not the place of the federal court to adjudicate how the party conducts its caucuses.

"State Democrats have a First Amendment right to association, to assemble and to set their own rules," Mahan said, encouraging the two sides in the suit to work out their differences.

"We aren't voting here, we're caucusing. That's something that parties decide," he said. It is "up to the national party and the state party to promulgate these rules and enforce them."

Read more in Major Garrett's Bourbon Room.

Click here to read more about the Clinton campaign's response from FOX News embed producer Aaron Bruns.

Six Democrats and the Nevada State Teachers Union, whose members have ties to Hillary Clinton's campaign, sued to shut down the nine sites that had been approved by the Nevada Democratic Party and Democratic National Committee.

The goal of the plan was to give housekeepers, waitresses, bellhops, restaurant workers and thousands of others who work on the Las Vegas Strip a chance to participate in the midday caucuses rather than take time off to return home to neighborhood precincts or skip the vote altogether.

But the suit argued that the at-large sites would give casino and hotel workers too much say in choosing the 10,000 delegates to the state's presidential nominating convention because of a formula that assigns one delegate to every 50 registered voters in Clark County, but uses a different ratio for those attending the at-large caucuses.

Opponents of the plan also argued that if some industries are allowed to caucus at work, even on Saturdays, then others, like school faculties and staffs, should as well.

The suit was filed shortly after the 60,000-strong Culinary Workers Union endorsed Obama, leading to charges that the Clinton campaign had a hand in the filing. That has been repeatedly and vehemently denied.

"While we were not involved in this lawsuit, and have always said that we would play by the rules that we’re given, it has always been our hope that every Nevadan should have equal access and opportunity to participate in the caucus.  Make no mistake -- the current system that prohibits some shift workers from being able to participate, while allowing others to do so, would seem to benefit other campaigns.  More importantly it is unfair," said Clinton campaign spokesman Jay Carson.

The Obama campaign issued a statement shortly after the ruling expressing its satisfaction with the decision and taking a shot at Clinton.

"We're glad that the Nevada court upheld the Nevada Democratic Party's caucus plan which encourages voter participation. While the Clinton camp clearly believed the voices of workers should be silenced in service of their perceived political interest, they enjoyed a 25-point lead two months ago and have much of the party establishment in their camp. So, despite their inherent advantages we are pleased this should be a close and competitive contest Saturday," said Obama campaign spokesman Bill Burton.

Obama, Clinton and John Edwards are running neck and neck in state polling, and Saturday's vote, the first contest to involve a large cross-section of minority voters, could be a good indicator of where the tight Democratic presidential race is going.

FOX News' Major Garrett contributed to this report.