“At times it’s lonely being a Democrat in Wyoming,” John Millin, the chairman of the Wyoming Democratic Party, said this morning.

Not today.

By 7:30 a.m., an hour and a half before the Laramie County caucus was set to begin, the line to enter the caucus site snaked for blocks through downtown Cheyenne.

Betty Jo Beardsley, a party aide, glanced at the throng of people swarming the registration table.

Is turnout higher than expected?, she was asked.

“Oh, God,” she replied.

No official word on the numbers yet. But in Laramie County, population 80,000, officials expected at least 2,000 people to show up at the caucus.

Inside the wood-paneled auditorium, caucusgoers waved signs, stomped their feet and cheerfully taunted each other like fans in the bleachers at a football game.

“Ohhhh-baaah-maaaaa!” a deep voice rang out from the front of the auditorium.

“Hill-a-REE! Hill-a-REE!” the chant answered.

The Obama people tried another tack. “Yes! We! Can!” they shouted. “Yes! We Can!”

“Hill-a-REE! Hill-a-REE!” Mrs. Clinton’s supporters answered, somewhat weakly.

The caucus will be conducted with paper ballots, unlike the traditional caucus format where supporters stand in groups according to their favored candidate.

Mr. Millan said most counties throughout the state would conduct their caucuses with paper ballots, and the results would start to be posted online in the early afternoon.

“I can hear the energy,” said Mr. Millan said, who is a supporter of Mr. Obama but left his button at home. “It feels like people are loving this whole thing.”

Vernice Sack, 80, and her husband, Paul Sack, 83, said it was the first caucus they have ever participated in. “I think he’s just great,” Mrs. Sack said of Mr. Obama. “He tells the truth.”

Phyllis Salzburg, of Cheyenne, said she would cast her ballot for Mrs. Clinton. “I think she has the clout, the power, and it’s about time the United States has a woman president.”