WASHINGTON — Senator Elizabeth Warren has built her following in part by taking pictures with thousands of voters deep into evening after campaign events, but her dinner audience here one night last month was far smaller. And Ms. Warren’s guests were more interested in hearing, and politely challenging, her campaign pitch than eagerly capturing the moment for posterity on their iPhones.
Addressing a few dozen members of the Congressional Progressive Caucus at a Chinese restaurant a few blocks from the Capitol, she laid out her case for why she could unify Democrats, emphasized that she was not hostile to properly run businesses and made a soft sell to the lawmakers to support her presidential bid.
“She said, ‘Nobody could do this alone, I will need your help,’” recalled Representative Chellie Pingree of Maine, who attended the gathering and said Ms. Warren “was great.”
But just under a month since the family-style meal, the Massachusetts senator has the same small number of endorsements from congressional colleagues beyond her home state as she did beforehand: three.
Ms. Warren is expected to reveal additional support from Democratic officials this week in conjunction with Tuesday’s CNN/New York Times debate and the release of her smashing third-quarter financial disclosure. Yet her growing crowd sizes, soaring fund-raising and surge to the top of a number of national and early-state polls only shine a brighter light on one of the most revealing elements of this primary: the widening gap between the preferences of many Democratic voters and the lawmakers who represent them.
Ms. Warren is now a clear front-runner in the race for her party’s nomination, yet just under four months before the leadoff Iowa caucuses she lacks the support of a single governor, big-city mayor or fellow senator outside Massachusetts.
She does have the backing of the Working Families Party, an influential liberal group, and yet she also has fewer total endorsements from state legislators in Iowa and New Hampshire than Senator Cory Booker, who registers in the lower single-digits of surveys and last month had to beseech donors to give him enough money to sustain his stagnant campaign.
The apparent lag between Democratic activists and Democratic elected officials, which comes nearly four years after President Trump’s stunning outsider’s capture of the Republican nomination and Senator Bernie Sanders’ surprisingly potent candidacy in the Democratic primaries, has done little to slow Ms. Warren’s momentum.
Yet the reluctance of Democratic lawmakers to embrace Ms. Warren’s campaign this deep into the year, after she has plainly emerged as a leading candidate, illustrates both the lingering reservations party elites have about her general election prospects and her unique positioning in this race.
“Racing to the left is not really speaking to the needs of people in the heartland,” said Chicago Mayor Lori Lightfoot, who expressed alarm about scrapping private health insurance, urged the candidates to focus on “pocketbook issues” and, when asked if Ms. Warren could reclaim the Midwestern states Mr. Trump captured in 2016, paused before saying: “I’m not sure.”
Ms. Warren is politically neither fish nor fowl.
She is not an anti-establishment insurgent in the style of Mr. Sanders, who were he in the position Ms. Warren is now would almost certainly have inspired a Stop Bernie campaign funded by a petrified donor class. But with her refusal to raise money among rich contributors, her unabashed populism and her pre-Senate roots in academia, she is hardly a Clinton-style creature of the Democratic political class.
As a result, many party officials are neither rushing to oppose her nor racing to her side, instead staying on the sidelines and doing what politicians often do when they are uncertain of what choice to make: buying time.
“It’s easier to wait, you keep your relationships good,” said Representative Deb Haaland of New Mexico, one of the few lawmakers who is supporting Ms. Warren, noting that some of her colleagues are loath to offend their friends in the race by choosing a candidate.
Reinforcing this instinct toward caution is the fluid nature of a primary still large enough to feature 12 candidates on the debate stage this week as well as the high stakes of next year’s general election.
“You had two candidates last time,” said longtime Representative Rosa DeLauro of Connecticut, referring to the Sanders-versus-Hillary Clinton race. “People want to see this unfold.”
Thanks to his decades-long relationships and the perception in some quarters that he would be a strong candidate against Mr. Trump, Joseph R. Biden Jr. has picked up the most support from Democratic lawmakers of any of the presidential hopefuls. But his uneven performance as a candidate this year and Mr. Trump’s daily barrage of attacks on him have left some party officials wondering just how safe a pick he is in 2020.
“People are concerned about Joe, but they ask: Is Elizabeth electable?” said former Senator Heidi Heitkamp of North Dakota, explaining the dilemma. “So a lot of people are just keeping their powder dry because they have not decided who can best run against Trump.”
Defeating a president who may be the first incumbent to seek re-election after being impeached should be the party’s overriding focus, said Gov. J.B. Pritzker of Illinois.
“I genuinely feel our republic is in danger,” Mr. Pritzker said.
A longtime donor who often immersed himself in primaries before he entered politics, Mr. Pritzker said he was staying out of this race for the time being in part because he was still stung by 2016, when some of Mr. Sanders supporters protested what they saw as his mistreatment by Mrs. Clinton and her establishment-aligned supporters.
“When he didn’t win people folded their arms and stayed home or they voted for Jill Stein or Gary Johnson,” said Mr. Pritzker, alluding to two of the third-party candidates whose votes helped cost Mrs. Clinton the election.
He’s not the only Democrat who has the echo of the Sanders-Clinton race still throbbing in their ears nor the only one determined to avoid alienating any of the supporters of this cycle’s candidates.
“Many believed the primary was rigged in favor of Hillary Clinton,” Representative Darren Soto of Florida said. “There is a feeling among many of us that we need to have a broad and diverse field, plenty of debates and let the primary voters decide on their own.”
What few lawmakers will say, at least publicly, is that wading into the race can also come with a cost: they run the risk of angering the eventual nominee if they support a losing candidate and they also invite complaints from their own constituents or donors, who may have a different preference.
What’s more, they also have to be mindful of their own political branding and how they align themselves.
“Politicians are different from voters,” said Donna Brazile, the longtime Democratic strategist and former party chair. “They have to say, ‘How does this fit with my agenda, my district?’” In Ms. Warren’s case, even one of her biggest boosters, Ms. Haaland, conceded it was easier for her to step out early because of the progressive nature of her district.
“Some folks they’re just like, ‘I better stay out of it for a while because of my district,’” she said of her House colleagues.
And it’s not just lawmakers who are taking a wait-and-see approach. Powerful liberal interest groups, including much of organized labor, are also hanging back, which only prompts the politicians to believe it’s safer to remain mum.
“That would make a difference if they came out,” Representative Dina Titus of Nevada said of unions. “They’re all being coy, too.”
Ms. Titus said she planned to get behind a candidate later this year, but her state, the third to vote in next year’s primary, illustrates just how many party elites were remaining neutral: Nevada’s governor, two senators, three Democratic House members and longtime boss, former Senator Harry Reid, have all refrained from endorsing a candidate.
Representative Jamie Raskin of Maryland said that he had also been “drawn in different directions in this race,” noting that he wanted to make a decision that’s both “passionate and strategic.”
But after having lunch in Washington last month with Ms. Warren and her husband, Bruce Mann, Mr. Raskin said he planned on endorsing the senator.
“If all she had to her name was senator from Massachusetts she would not be an ideal candidate,” he said, before citing Ms. Warren’s record as a consumer advocate and critic of Washington self-dealing. “As a candidate of public integrity and honesty in government, she has a very powerful story to tell at a time of boundless Republican corruption and lawlessness.” What’s more, Mr. Raskin said, “She made a very eloquent and personal pitch to me.”
As for Ms. Pingree, she said she was “watching the wisdom, the perspective of the public” and was eager “to see who people get excited about.”
She will also have a chance to gauge the views of her colleagues. When Congress comes back from its recess this week, Ms. Pingree said she and the other House Democrats who live in her Washington high rise planned on having a debate watch party in the building’s common room.