UPDATE 2-US court allows casino vote that may boost Obama

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By Adam Tanner

LAS VEGAS Jan 17 (Reuters) - A federal judge on Thursday allowed Nevada Democrats to hold presidential voting in casino hotels on the Las Vegas Strip, potentially helping Sen. Barack Obama in the next round of the campaign on Saturday.

For the first time, Nevada Democrats planned to set up nine locations for Saturday's vote so casino shift workers, who are largely represented by a union that endorsed Obama, could attend caucuses and vote for a presidential candidate.

A teachers' group filed a lawsuit saying the fact that only casino workers could vote at their workplaces was unfair, but Judge James Mahan of the U.S. District Court for Nevada disagreed and rejected a temporary injunction.

A large turnout of casino workers could boost Obama, of Illinois, in his tight race against New York Sen. Hillary Clinton because he is backed by the Culinary Union, which represents 60,000 dishwashers, cooks, cleaners and other hotel service workers.

Other Nevadans will meet in locations near their homes to vote in the series of state-by-state contests to choose Democratic and Republican nominees.

Similar to Iowa, the voting in Nevada is done in caucuses, or gatherings, rather than by individual polling.

The Culinary Union is the state's most influential labor group and its activists are talking to members in workers' cafeterias in the famed Strip hotels and knocking on doors urging its members to turn out for Obama.

OUT IN THE OPEN

Unlike presidential primary elections in most U.S. states, the Nevada Democratic caucus requires participants to stand in the open in groups to support the candidates.

Any member not backing the union choice would be visible -- a dissent that would be especially clear in voting on the Strip instead of locations near homes.

Clinton and her husband, former President Bill Clinton, have in recent days voiced concern about the fairness of the Strip caucuses, while Obama has been displeased by the lawsuit that came almost immediately after he won the Culinary Union endorsement last week.

Republicans are also holding caucuses in Nevada on Saturday but will not have any sites at the casino hotels.

"The Democrats can set up their own rules just as the Republicans can," Judge Mahan said. "It is not up to some federal judge to come along and say, I don't like that."

As to any confusion in the rules, Mahan quoted U.S. humorist Will Rogers: "I'm not a member of any organized group. I'm a Democrat."

The judge said he would have been interested in intervening in the party's rules if they discriminated against blacks, women or Jews.

Some members of the culinary union suspected the case was motivated by Clinton supporters, but the head of the teachers' organization denied that.

"Our association has not endorsed any candidate," said Lynn Warne, president of the Nevada State Education Association.

Warne added that she only learned details of the casino voting plan last week. (Editing by Alan Elsner)