LAS VEGAS » A special Saturday night Republican caucus here intended to accommodate Orthodox Jews who could not vote before sundown became the scene of controversy and confrontation after caucusgoers were told that for admittance, they had to sign a legal declaration under penalty of perjury that they could not attend their daytime caucus because of "my religious beliefs."

Many supporters of Rep. Ron Paul of Texas protested when given the declaration to sign. They had arrived at the polling place — a school here named after its benefactors, the casino billionaire Sheldon Adelson and his wife, Miriam — after they received an automated phone call from the Paul campaign saying voters unable to attend their regular caucuses could go to the night meeting.

And Paul campaign aides later said that anyone who had missed their earlier caucuses during the day for any reason should have been allowed to vote, and suggested that what they described as the "religious test" at the caucus would lead to lawsuits.

Mike Dicicco, a Paul supporter who drove 30 minutes from Henderson, Nev., said he was asked whether he was Jewish by a poll worker. Dicicco said he had received the automated campaign call and could not vote earlier because he had to work, not because of religious reasons.

"Why wouldn’t I be able to vote just because I’m not Jewish?" he said.

Sharon Saska, who said she arrived too late to her regular caucus to vote, was refused entry to the night caucus because she would not sign the declaration. If she had, she would have been committing perjury, she said, because religious beliefs had not kept her from voting earlier. She said she had planned to support Newt Gingrich.

A number of other caucusgoers suggested that they signed the declaration even though they did not have a religious reason for not voting earlier.

Holding the special caucus seems to have been a reasonable and appropriate attempt to accommodate people who could not vote earlier for religious reasons, said Richard L. Hasen, a professor specializing in election law at the law school at the University of California Irvine.

But, he said, the controversy points out the shortcomings of caucuses as compared with primaries.

"It started off as an admirable thing, but because of concerns of the integrity of the process, it devolved into something uglier," Hasen said. "More generally, it shows a lack of professionalism in the way many of these caucuses are handled."

Those who could not vote for religious reasons during the day, he said, had a reasonable argument that some accommodation had to be made, which could have included changing the date. But using the legal declaration raises the question whether other nonreligious groups are also entitled to the accommodation, and, he said, "I’m not sure how the courts would answer that question."

"When a party runs a caucus, we treat the party like a government entity, so they cannot discriminate," Hasen added. "You could not have a whites-only caucus, for example."

Top officials from the Paul and Romney campaigns were on hand to observe the gathering, including Mitt Romney’s campaign counsel, Benjamin L. Ginsberg; Paul’s Nevada chairman, Carl Bunce; and Paul’s deputy national campaign manager, Dimitri Kesari.

Officials from the Clark County Republican Party defended the declarations and the special caucus, saying that the declaration did not single out any one faith — Jewish or otherwise — and that anyone who had a religious objection to voting earlier in the day could vote at the special caucus. They said that their election lawyers had signed off on the use of the declaration, and they also noted that many Seventh-day Adventists also could not vote during the day because of religious reasons.

"This was designed for those who could not participate today due to religious observances," said Dave Gibbs, the chairman of the Clark County Republican Party, in an interview on Saturday. "That’s all this is."

But some Paul officials suggested that the declaration was an unlawful injection of religion into the electoral process.

Bunce, the Paul campaign’s Nevada chairman, said dozens of people had declined to sign the declaration and had been refused admittance to the caucus. An official from the local Republican Party said no more than three people were turned away after they refused to sign.

"No one should have to face a religious test to vote," Bunce said, adding that election officials who blocked people from voting because they did not sign the declaration could be "getting a lawsuit."

Nevertheless, Paul supporters packed the caucus and won handily. According to local party officials, Paul received 183 votes; Mitt Romney, 61 votes; Newt Gingrich, 57 votes; and Rick Santorum, 16 votes.

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