With the exception of Nevada, Senator Hillary Rodham Clinton has lost to Senator Barack Obama in every state that has held Democratic caucuses instead of primaries.
She is not giving up on Wyoming so easily.
On the eve of the Saturday caucuses here, Mrs. Clinton arrived for rallies in Cheyenne and Casper, trying to seize on the momentum from her primary victories in Ohio and Texas on Tuesday to pull off a rare caucus victory. Her appearances came after her husband, former President Bill Clinton, campaigned in the state on Thursday.
Speaking at a community college in Cheyenne on Friday, Mrs. Clinton questioned Mr. Obama’s experience and promoted her time as first lady, saying she had “been in the Oval Office a few times.”
“I think it is an advantage that I’ve been there,” she said. “And I know what happens on both ends of Pennsylvania Avenue.”
She added pointedly, “You know, I have a full term in the Senate under my belt.”
But Mr. Obama, speaking 140 miles to the north, in Casper, turned Mrs. Clinton’s experience back on her, strongly criticizing her 2002 vote to authorize the war in Iraq. He was responding to a comment Mrs. Clinton made earlier in the day that questioned his commitment to end the war.
“If it had been up to me, we would have never been in this war,” Mr. Obama said, speaking over loud applause. “It was because of George Bush with an assist from Hillary Clinton and John McCain that we entered into this war.”
Accustomed to being ignored in an overwhelmingly Republican state, Democratic officials here were gleeful that both Mr. Obama and Mrs. Clinton were campaigning heavily a day before the caucuses.
Mr. Obama has campaigned in virtually every state that has held a primary or caucus this year, and his resulting victories in a broad swath of states are a major reason he has a lead over Mrs. Clinton in delegates. He has been virtually uncontested in several states, with little presence from the Clinton campaign in previous caucuses in Idaho, Kansas, Nebraska and Utah.
The Clinton campaign, by contrast, has suggested that caucuses are undemocratic, unrepresentative and controlled by party activists. Mrs. Clinton has even invoked her husband to defend her losing record in caucus states, saying that he “never won caucuses.”
So her presence in Wyoming, along with her two leading surrogates — her husband and her daughter, Chelsea — underscores how the race has become a pitched battle for each of the remaining 12 contests, which could help determine the Democratic nominee.
Yet Mrs. Clinton on Friday renewed her criticism of the caucus process, telling an audience in Cheyenne that “it isn’t any secret that a lot of people who vote for me have never caucused for me.”
“It’s not an election,” she added.
Mrs. Clinton arrived less than 24 hours after her husband and daughter had left the state. Mr. Clinton campaigned throughout the state on Thursday, filling an auditorium to capacity at the University of Wyoming in Laramie, while Chelsea Clinton spoke to several hundred college students in Casper. “Clinton Blitzkrieg,” declared The Wyoming Tribune-Eagle in a banner headline on Friday. “We think it’s got to be the first time in history that we’ve had a former president, a former first daughter and a former first lady all in the state of Wyoming within two days,” said Kathy Karpan, a former Wyoming secretary of state and a Clinton supporter.
State officials described the race as extremely tight, despite the fact that the Obama campaign had a head start in terms of organization. By Friday, the two campaigns seemed well matched on that front, said Bill Luckett, a spokesman for the Wyoming Democratic Party.
“The Obama staffers were in the state first,” Mr. Luckett said. “But the Clinton staffers did arrive shortly after that. And at this point, they’ve both got really visible presences in the state.”
The Obama campaign has been organizing in Wyoming for a month, and it has five offices in the state, in Casper, Cheyenne, Laramie, Rock Springs and Sheridan. In the last month, aides said, organizational meetings had been held in nearly every county. This week, Mr. Obama began running television and radio commercials in Wyoming.
The Clinton operation set up shop on Feb. 25, when it opened offices in Cheyenne and Casper. Currently, there are 15 paid staff members and more than 400 volunteers statewide, said Ben Kobren, a campaign spokesman.
“We’re working as hard as we can,” Mr. Kobren said. “We think there’s strong support here, and we’re looking for a strong Saturday.”
Mrs. Clinton has run one radio advertisement, a 60-second spot focusing on health care and the Children’s Health Insurance Program.
Wyoming will award 12 delegates based on the results of the caucuses. Democrats, independents and Republicans can vote in the caucuses, and state officials estimated that 7,000 of the state’s almost 60,000 registered Democrats would participate.
Julie Bosman reported from Cheyenne, Wyo., and Jeff Zeleny from Casper, Wyo.