Mr. Vassiliadis said that dynamic had contributed to opening the door, among moderate voters, to former Mayor Pete Buttigieg of South Bend, Ind., who has been aggressively ramping up his presence in Nevada, as well as Senator Amy Klobuchar of Minnesota, who surprised with a third-place finish in New Hampshire.
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 M. 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, criticism that Mr. Biden amplified in an interview on NBC’s “Meet the Press” over the weekend. “So we have intensified our precinct captain training for the Nevada caucus. We also have increased our legal presence.”
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.”