LAS VEGAS — On Friday afternoon, Joseph R. Biden Jr.’s campaign manager, Greg Schultz, convened a conference call with supporters to outline a path forward following two bruising losses in Iowa and New Hampshire.
The campaign, Mr. Schultz made clear on the call, was banking on finishing in at least second place in the upcoming Nevada caucuses, a contest that will offer the first major test of Mr. Biden’s assertion that he can uniquely assemble a diverse coalition.
Left unsaid: Nevada will also show whether Mr. Biden, the former vice president, can revive his campaign after his first two finishes sent his national poll numbers plummeting, put his donors on edge and jeopardized his standing even in his perceived firewall state, South Carolina.
“First would be wonderful, but us getting a second place I think does the work that we need to do to win South Carolina,” Mr. Schultz said. “We win South Carolina, we’re going to have ended the first four contests likely with a delegate advantage.”
He added, “I think the Democratic Party will sigh a collective sigh of relief when we finish second or better in Nevada.”
With only days until Saturday’s caucuses, Mr. Biden’s campaign is racing to make Nevada the state that begins his comeback — not the one that accelerates a plunge from which he never recovers.
Yet such an outcome is hardly assured.
Mr. Biden struggled to excite Democrats in Iowa and New Hampshire, a crucial factor in his early losses. But in Iowa especially, poor organizing played a significant role, raising questions about how he will fare in Nevada, which, like Iowa, also holds caucuses instead of a traditional primary election.
“His ground game has been here a while and had staff here for a long time, but similar to Iowa, they took things a little for granted that he was the front-runner, that he had 99 percent name ID,” said Megan Jones, a political strategist in the state who worked for Harry Reid, the former Nevada senator and Democratic majority leader. “They have been quickly making up for lost time because they know it’s a make-or-break situation.”
Mr. Biden’s campaign has redeployed staff from later-voting Super Tuesday states to lend extra manpower in Nevada and now says it has more than 130 staff members on the ground. He is leaning on a roster of high-profile endorsers in the state, and he is campaigning here day after day, putting a particular focus on outreach to voters of color.
“He knows that he cannot take the minority vote, the African-American, Latino and Asian-American vote, for granted,” said Representative Steven Horsford, Democrat of Nevada, who endorsed Mr. Biden last week. “He will do something, once he’s the president, to actually deliver for the American people and for voters of color who sometimes feel taken for granted and only get appealed to during an election. There are some candidates who literally right now are just now engaging in Nevada.”
Mr. Biden has been airing television ads in Nevada focused on gun violence as well as on health care, but he has been significantly outspent by Senator Bernie Sanders of Vermont, whose fund-raising has far outpaced Mr. Biden’s. Mr. Biden also faces competition from the billionaire Tom Steyer, whose ad spending in the state dwarfs that of any other candidate.
Mr. Biden is expressing a much sunnier outlook about how he will fare in Nevada compared with New Hampshire, where he predicted four days before the primary that he would “probably take a hit.” At a fund-raiser in New York City last week, he said he expected to finish first or second in Nevada.
At campaign stops over the past few days, Mr. Biden has not overhauled his message or unleashed sharpened attacks on his rivals, though he has put a fresh emphasis on certain key issues. He has highlighted his record on gun control, an important issue to many Democrats in a state where the deadliest mass shooting in modern American history took place. He has also assailed a 2005 law that shields gun manufacturers from liability lawsuits — an implicit shot at Mr. Sanders, who voted in favor of it as a House member.
In addition, Mr. Biden has stressed that his health care plan would allow union members to keep their current insurance — a major contrast with Mr. Sanders, who advocates “Medicare for all.” But he suffered a setback last week when the powerful Culinary Workers Union Local 226 announced it would not make an endorsement in the race, though the union’s secretary-treasurer cited him by name at a news conference and said, “We know he’s been our friend.”
At a campaign event over the weekend, Mr. Biden, apparently undeterred by the union’s decision, cited his support from labor unions and then added, “I know in their hearts the Culinary Workers are there — in their hearts.”
Mr. Biden can still be unfocused at times, a problem that has hindered him throughout the race. During a rally in the Las Vegas suburb of Henderson on Friday evening, he declared that he did not want to use the teleprompters that had been set up for him, and later wound up talking to the crowd about Chinese land that is polluted with the metal cadmium. A minute later, he brought up an obscure government agency, the Defense Advanced Research Projects Agency, or DARPA. And a minute after that, his speech was over.
In those closing moments, he never mentioned the caucuses or explicitly asked attendees to support him.
But his time on the campaign trail in Nevada has also shown the promise of more diverse states. During a visit to a Black History Month festival on Saturday, he was greeted with enthusiasm by attendees as he made his way through the crowd. Before he spoke onstage, the M.C. referred to him as President Biden and offered to serve as the host at his victory party.
Mr. Biden was introduced by one of his newest endorsers, Mr. Horsford, who told the crowd that Mr. Biden “has our back” and added, “I know it because he had Barack Obama’s back as vice president for eight years.”
And so far, there is simply not the same kind of widespread criticism of his Nevada caucus organization that dogged him in Iowa. He has been aided by Yvanna Cancela, a state senator who is working as a senior adviser to the campaign, and Jennifer O’Malley Dillon, a former Obama campaign official who ran former Representative Beto O’Rourke’s presidential campaign and is assisting in a volunteer capacity.
But the cloud of doubt resulting from his poor showing in the first two contests still lingers. Billy Vassiliadis, the chief executive of the marketing and advocacy firm R&R Partners, described a highly fluid race, with many voters still assessing which candidate stands the best chance of defeating President Trump. Mr. Biden’s fourth-place finish in Iowa and fifth-place result in New Hampshire was jarring even to some independent-minded Nevadans, he said.
“For the great majority of the voters, they don’t dig deep and really consider the fact that Iowa and New Hampshire probably weren’t the vice president’s best playing field, and that the vice president needs a more sort of diverse voter base,” he said. “There was an expectation that the vice president was going to finish higher. When they saw that finish, it kind of shook what they were confident in.”
Mr. Biden’s allies have played down the significance of Iowa and New Hampshire, and insist that Mr. Biden remains poised to perform strongly in more diverse states like Nevada.
“I love repositioning Joe Biden as the underdog,” said Mayor Eric Garcetti of Los Angeles, a national co-chair of Mr. Biden’s campaign, offering a glass-half-full assessment of Mr. Biden’s place in the race. “Democrats love underdogs. Americans love underdogs.”
And on the Friday call with supporters, Mr. Schultz pointed to changes the campaign was making, including engaging in more national news media interviews — something a number of top supporters had encouraged post-Iowa — and redirecting resources to Nevada and South Carolina.
“I think we did not adequately prepare for the chaos that was going to be at the various caucus locations, and, you know, there’s one candidate, in particular, whose supporters do not make things easy because of the antics they pull,” he said, a reference to the supporters of Mr. Sanders. “So we have intensified our precinct captain training for the Nevada caucus. We also have increased our legal presence.”
Still, the poor early showings have created skepticism among some voters here. When Mr. Biden took questions from the audience at a campaign event in Reno on Monday, a supporter lavished praise on him, but then asked, pointedly: “What the heck is going on with your campaign?” Mr. Biden responded that it was “a good question” and “a legitimate question,” before noting Iowa’s lack of racial diversity.
Barbara Bell, 64, a retired county employee who came to the rally Mr. Biden held in Henderson, said the contests in Iowa and New Hampshire had left her concerned about his chances — even as she struggled to discern what went wrong for him.
“To me, they’re little white states,” she said. “I don’t know what gets to them or what turned them on. I can’t figure it out.”
Ms. Bell worried aloud about moderate Democrats splitting their votes among multiple candidates while Mr. Sanders thrives. She and her husband were a perfect example: She planned to support Mr. Biden, with Senator Amy Klobuchar of Minnesota as her second choice, while he preferred Ms. Klobuchar over Mr. Biden.
Asked her level of confidence that Mr. Biden would win the nomination, she responded, “Well, it was a lot higher a month ago.”
Thomas Kaplan reported from Las Vegas, and Katie Glueck from New York.