Why Populist Democrats Have Gained the Upper Hand in the Primary Race

As next week’s debate looms, polls and donor contributions suggest a party seeking candidates for 2020 who will push the boundaries, while moderates argue they can beat President Trump.

With a crucial debate looming next week in the Democratic presidential primary, the party’s populist wing appears increasingly in control of the race — rising in the polls, stocked with cash and with only a wounded leading candidate, Joseph R. Biden Jr., standing in its way.

Several slow-building trends have converged to upend the race over the last few weeks: Senator Elizabeth Warren’s steady ascent in the polls has accelerated. Both she and Senator Bernie Sanders, a fellow progressive, have raised immense sums of money from small donors online, dominating the Democratic field and each collecting about $10 million more than Mr. Biden in the last quarter. And Mr. Biden’s numbers have gradually slipped in a way that has alarmed his supporters.

The race is far from over: All three of the top candidates — Ms. Warren, Mr. Biden and Mr. Sanders — have a path to victory, and there is still time for longer-shot candidates to make a real run at the nomination. The CNN/New York Times debate in Ohio on Tuesday is likely to test Ms. Warren’s status as an emerging front-runner, subjecting her to new criticism from her fellow Democrats on matters ranging from health care policy to trade and the role of the government in overseeing the economy. Above all, she may need to allay lingering reservations about her appeal to swing voters in the general election.

And Mr. Biden signaled on Thursday night that he will come into the debate fighting. “One of the problems I’m finding, I’ve got to be more aggressive,” he said at a fundraiser in Los Angeles. He then used a roundabout example to explain that debate time restraints don’t allow time for lengthy answers.

“When someone says, you know, you know, ‘are you still beating your wife?’ And, and I go, ‘I have a long explanation’ and they say ‘you got 30 seconds to answer.’ And you say ‘No. And then, wait a minute, what’d I just say? No, I’m not still beating my wife.’ But so, I’ve had, I’ve had some difficulties,” he said.

If Tuesday’s debate could break in any number of directions, what may be resolved is the overall mood of Democratic primary voters, and whether they are more inclined to seek a politically cautious nominee who promises to restore normalcy in Washington, or a more confrontational standard-bearer with an ambitious and disruptive reform agenda. It is candidates in the latter category who now control the bulk of the financial might in the race, and are best positioned in most of the early primary states.

Anna Greenberg, a Democratic pollster who is not aligned in the primary, said an “anti-establishment” current had plainly taken hold, with voters rewarding candidates for defying the conventional limits of political debate and “pushing boundaries in really productive ways.” She pointed not only to Ms. Warren and Mr. Sanders but also to former Representative Beto O’Rourke, who has embraced a new political identity for himself as a gun-control activist and a critic of his own party’s relatively cautious platform on the issue.

“Across the board, whether it’s Beto talking about assault weapons or Warren and Sanders talking about Wall Street,” Ms. Greenberg said, “it does feel like there is a shift in the party that is kind of new.”

Ms. Greenberg said there was still space for Mr. Biden to run a strong campaign because of the way voters perceive his values and character. Americans, she said, believe Mr. Biden “cares about people and working class people, regular people, and that’s not an insignificant asset.”

Yet it has been Ms. Warren, rather than Mr. Biden, who has consistently gained strength. Campaigning on a message of purging corruption in Washington and restructuring the economy, Ms. Warren has closed Mr. Biden’s lead in the polls every week since the beginning of the summer and is now in a position to upset him in both Iowa and New Hampshire, the first two states to vote.

Mr. Biden remains a strong contender for the nomination, largely because of the support he collects from African-American voters. But he has struggled for months to articulate a clear vision for the future and has relied heavily on Democratic nostalgia for the Obama administration. In recent weeks, he has been consumed in a grisly political clash with President Trump.

So far, the support Mr. Biden has lost does not seem to have gone to another moderate, like Mayor Pete Buttigieg of South Bend, Ind. Only Ms. Warren has been moving up in the national polls, suggesting either that Mr. Biden’s lost supporters have defected to her camp or that they have become undecided altogether.

If Ms. Warren has become the leading liberal standard-bearer, Mr. Sanders has been a steady third in national polls and his fund-raising power is likely to keep him among the most formidable competitors in the race. Yet his campaign has been grappling with the implications of Mr. Sanders’s heart attack in Las Vegas last week, a medical emergency that landed him in the hospital and has kept him off the trail for days.

He has sent mixed signals about his path forward, first indicating that he would scale back his campaign schedule and then defiantly reversing that suggestion.

It is unclear whether Mr. Sanders’s physical condition will affect his poll numbers: He has a solid base of support nationally and few other candidates believe his core followers will be easily dislodged. There is at least a new degree of uncertainty about whether he will be in a strong position to vie for liberal Democrats who have already been migrating toward Ms. Warren.

Nearly all of the candidates feel pressure to do something in the Ohio debate to stop the race from becoming a contest entirely defined by a Warren-Biden rivalry, either by inflicting direct damage on Ms. Warren’s campaign or by outflanking her as an alternative to Mr. Biden. The ongoing impeachment inquiry targeting Mr. Trump has only added to the pressure on the Democratic field, since the tumult in Washington is likely to leave voters with even less time to devote to reviewing underdog options.

Mr. Buttigieg in particular has been moving assertively in recent weeks to position himself as a center-left alternative to both Mr. Biden and Ms. Warren, using his considerable war chest to run television ads in Iowa.

Several other candidates of different ideological stripes are counting on Iowa for a breakthrough, including Senators Kamala Harris, Cory Booker and Amy Klobuchar. A wild-card joining them onstage will be a new contender, Tom Steyer, a former hedge fund investor who has spent lavishly from his personal fortune to brand himself as a reform-minded outsider.

For Ms. Warren, meanwhile, the debate may help reveal whether she can consolidate her gains across the Democratic Party. On Wednesday, she campaigned in South Carolina, where she has so far struggled to gain traction with the African-American voters who largely decide the primary there. To cement her status as a front-runner, she may have to win over a range of constituencies torn between their interest in her ideas and a more cautious political calculus that draws them to Mr. Biden.

One of those voters is Ohio’s former governor, Ted Strickland, the only Democrat to hold that office this century. Like many Democratic voters, Mr. Strickland, a populist with close ties to organized labor, said he saw Mr. Biden as the safer bet for the general election but found it hard to resist the appeal of Ms. Warren’s proposals, most of all her plan for a new tax on vast private fortunes.

“I think there may be something to the electability issue for Mr. Biden, in Ohio,” Mr. Strickland said. “But if I could just choose to put someone in the presidency — if that was my choice alone — it would be hard for me to pass up Elizabeth Warren.”

Mr. Strickland said he had spoken with Mr. Biden recently and saw him as a seasoned diplomat and a reliable “economic progressive.” But Ms. Warren, he said, was gradually easing voters’ reservations about her ability to go up against Mr. Trump by talking about policy issues “in ways that are easily understood.”

Mr. Biden remains a clear favorite in just one of the early states, South Carolina, and his advisers have predicted that he would fare better in larger, more diverse states that vote later in the calendar. He is counting, in particular, on older and more moderate African-American voters to hold back the party from stampeding toward a more ideological liberal candidate. In 2016, black and Latino voters helped Hillary Clinton withstand a persistent primary challenge from Mr. Sanders.

Yet scattered polling in the later states has largely followed the national trend: Last week, for instance, the Public Policy Institute of California released a poll finding a statistical three-way tie in the nation’s most populous state between Mr. Biden, Ms. Warren and Mr. Sanders.

Mark Baldassare, president of the institute, said there was no indication in his poll that the state’s diversity would represent a stumbling block for candidates on the left, as Mr. Biden is hoping. The primary debates would be crucial to determining Ms. Warren’s continued momentum, he said, because voters seemed to be using them for insight into the general election.

“It has become kind of a proxy for: How are these candidates going to do when they stand up next to Trump?” Mr. Baldassare said. “I think this will be Elizabeth Warren’s moment now, because if she is in the mix for front-runner, people are going to be testing her and seeing: How does she do? How does she do when she has to be on defense?”

Sources: Polling data from ABC News/The Washington Post, Reuters, Monmouth University, Quinnipiac University, Fox News, USA Today/Suffolk University of New Hampshire, CBS News/YouGov, CNN, The Des Moines Register, NBC News/The Wall Street Journal, Winthrop University. Numbers are through Oct. 10.