Ben Margot / AP

SAN FRANCISCO—Joe Biden is ostensibly the candidate of the Democratic establishment. But it was Elizabeth Warren—who’s built her career on trying to challenge the status quo—who spent the weekend wowing party insiders.

At this point in Warren’s campaign, it’s not a surprise anymore when she spends hours working a “selfie line” after a major event, as she did following two massive rallies she’s held in the past week. But it was a surprise when more than 150 of the Democratic Party’s biggest donors similarly lined up on Thursday night after her speech at a dinner here—and it struck even some of the Democrats waiting to take photos with her.

“These are people who should not like her,” said one attendee, who spoke to me on the condition of anonymity to avoid showing favoritism. “And they love her.”

The next day, at the summer meeting of the Democratic National Committee, party members were on their feet cheering when she took the stage for a brief address. When he spoke there, Senator Cory Booker of New Jersey seemed to land more applause lines overall. A few other candidates were also received warmly, including Senator Bernie Sanders of Vermont, who gave a notably conciliatory speech about the proud legacy of the Democratic Party that perhaps no one could have imagined him delivering after his burn-down-the-DNC campaign in 2016.

But it was the Massachusetts senator who got a standing ovation before she’d even said a word, and another as soon as she’d finished speaking. From the start, Warren’s campaign was built on the theory that she’s an outsider whom insiders can live with, and an insider who has credibility with outsiders—in 2016 terms, someone who can attract both Sanders and Hillary Clinton voters. Primary voting is months away. The DNC’s 2020 convention is almost a year from now. But on Friday afternoon, in the huge, bland hotel ballroom where the DNC meeting was held, Warren’s theory seemed to be working out.

She “stretches across a broad spectrum of Democrats,” said Don Fowler, a DNC chair in the 1990s, a longtime Clinton-family loyalist, and someone who’s been to more DNC meetings over more election cycles than most people in Democratic politics today. Explaining what he thinks her appeal is to establishment Democrats, Fowler told me that for all of Warren’s talk of “big, structural change”—by fundamentally reworking the economy—“she does not include in her presentation the implication of being against things, except the current president.”

Warren’s insider-outsider routine is one reason, Democratic operatives and analysts told me—and one another, in private conversations—that they’ve begun to see her as the odds-on favorite to win her party’s nomination. However, a few of the Democrats I spoke with noted that her positioning could become a trap: With Sanders and Warren expected to battle even more intensely in the coming months, the change-hungry part of the Democratic base might begin to ask why establishment insiders seem so comfortable with her.

Jay Jacobs, the chair of the New York Democratic Party, told me a few hours after Warren’s Friday speech that although his politics aren’t as far left as Warren’s, “there wasn’t a thing she said today that I could not have written.” Jacobs, who was made chair by the Biden-backing Governor Andrew Cuomo, added, “The times do call for bolder action.”

“I hope Sanders supporters see Warren’s broadening support as a good thing and won’t now cynically try to paint her as beholden to insiders, because she’s not,” said a DNC member who isn’t currently committed to any candidates and who spoke on the condition of anonymity. “We will see.”

Most of the Democrats I talked to didn’t seem especially upset that Biden did not attend the summer meeting. But they did have their suspicions about why he skipped it: Multiple state-party chairs and other attendees told me—speaking only on the condition of anonymity—that they assumed he was wary of receiving a less-than-wild reception compared with other candidates.

Asked for comment on those assumptions, the Biden spokesman Andrew Bates wouldn’t say whether they were correct or not, but he noted that the former vice president often attends DNC events. “This weekend he was in New Hampshire, where he had great events speaking directly to voters about the stakes of this election,” Bates said.

Just like every other group of voters, DNC members have their own interests, and Warren tried to appeal to the things that make them tick. In her speech on Thursday, she reminded the audience that in March 2018, she wrote $5,000 checks to each state party from her campaign account, part of an overall $11 million she raised for Democratic Party efforts. During the midterms, she also endorsed and campaigned for candidates across the country. Her work on behalf of other Democrats is likely helpful with the what-have-you-done-for-me-lately types who live for these major meetings of Democrats.

And even if most DNC members are staying studiously neutral in the primaries, several of them told me they like what they’ve seen in the massive ground operation Warren is assembling in the early-voting states. To those who spend their professional lives thinking about campaign mechanics, this is alluring.

“To her advantage, it appears as though she did not let the growing pains of the early stage of her campaign sidetrack her from creating an infrastructure,” said Trav Robertson, the Democratic Party chair in South Carolina, one of the early states where campaign action is already under way. “Her campaign’s been fascinating to watch,” he told me. “It’s a study of ‘Steady and slow wins the race.’”

Warren has made her detailed policy plans a core part of her brand on the campaign trail, and that approach seems to interest establishment Democrats too. After all, they’re the type of voters most likely to actually read those proposals.

Sanders “is providing more of economic aspirations; she’s providing more of a road map,” said Stuart Appelbaum, the president of the Retail, Wholesale and Department Store Union, the executive vice president of the United Food and Commercial Workers International Union, and a member of the DNC executive committee. “Even in this room, she comes across as practical, smart,” he said, standing in the hotel ballroom. “I think there is a sense of respect for her and the way she’s conducting her campaign.”

Do the opinions of party insiders even matter anymore? The answer is a resounding “maybe.” DNC members are among the superdelegates whose power in the presidential-nominating process was stripped last year. But all the people at the summer meeting are active and influential in local politics, and they have the potential to softly sway opinions in ways that could ripple out of their communities.

The DNC members won’t come together like this again for almost a year. The next meeting, announced on Saturday afternoon, is set for July 17, 2020, in Milwaukee—the day after the Democratic nominee delivers his or her acceptance speech at the next convention. Democrats have a history of summer flings with lefty insurgents ahead of presidential primaries—think Howard Dean in 2003 and Sanders in 2015. At least for now, though, Democrats seem to be having fun watching Warren.

“Most of all, she’s smart as shit,” Fowler told me as he tried to put his finger on why he and others like her. “You don’t want a dumb-ass president.”

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