Scott Morgan / Reuters

White working-class voters’ share of the electorate may be shrinking even faster now than in recent years, new data suggest. But that dynamic shows no signs of dampening the growing debate among Democrats about how heavily the party should focus on recapturing the blue-collar whites who have become the foundation of Donald Trump’s electoral coalition.

No choice in 2020 divides Democratic activists more than the question of whether the party needs a nominee best suited to winning back these white voters, who have been drifting away from the party for decades, or one best positioned to mobilize the party’s new alliance of minorities, young people, and white-collar whites, especially women.

The issue has crystallized around former Vice President Joe Biden’s entry into the 2020 race. His supporters and detractors alike have taken his candidacy as a proxy for the larger question of how Democrats can best rebuild a winning presidential majority. Few Biden backers would argue that at 76, with nearly a half century of public life and two failed presidential campaigns behind him, he brings some unique combination of personal qualities that was missing from the roughly 20 other candidates in the race. Rather, the central rationale for his candidacy is the argument that he’s uniquely positioned to recapture some of the working-class white voters who stampeded to Trump in 2016, particularly in the decisive Rust Belt states of Pennsylvania, Michigan, and Wisconsin.

The reverse is largely true for the younger liberal writers and activists, many of them women and people of color, who have recoiled from Biden’s candidacy over the past several weeks. In a stream of articles and essays as he approached the race, these critics partly objected to Biden’s record over his long career, particularly on issues relating to race and gender. (One pressure point: his handling of Anita Hill’s accusations of sexual harassment against now–Supreme Court Justice Clarence Thomas in 1991.)

But even more fundamentally, many of them have rejected the idea that Democrats should prioritize a nominee who can win back working-class whites. They believe Democrats instead should find a standard-bearer who embodies and energizes their emerging coalition. “Democrats treat the working-class, white voter as if they were white buffaloes—sacred entities,” the New York Times columnist Charles Blow wrote this week. “I say that the rest of your base … are watching with dual lenses of disappointment and dissatisfaction.”

Biden’s kickoff campaign rally at a teamsters’ union hall in Pittsburgh on Monday left no confusion about how heavily his campaign will stress his claim to blue-collar bona fides. Biden thanked a long list of unions, plaintively asked when Americans stopped noticing the people who do manual jobs, repeatedly praised “the dignity of work,” and declared of himself: “I make no apologies. I am a union man. Period.” Apart from the presence of more African Americans in the crowd and Bruce Springsteen on the rally’s soundtrack, nothing looked or sounded very different than it might have if Hubert Humphrey had delivered the speech in 1968.

Part of the backdrop of the intraparty Democratic debate is the surprising results from the latest Census Bureau data on who voted in 2018. Those numbers suggest that the long-term decline of working-class whites as a share of the electorate appears to be accelerating. Over the past five presidential elections, non-college-educated whites declined from 54 percent of the total vote in 2000 to 44 percent in 2016, according to calculations based on the census data by the nonpartisan States of Change project. The erosion reflects a society growing both more educated and more racially diverse: Over that period, whites with at least a four-year college degree grew slightly as a share of the voting pool, from 27 percent to 30 percent of the vote, while minorities jumped from just under one-fifth of voters to more than one-fourth.

The latest census results tracked a much more rapid decline for non-college-educated whites from 2014 to 2018, according to an analysis of the findings conducted on my behalf by the University of Florida political scientist Michael McDonald, an expert in voting participation. In 2018, whites without a college degree cast just over 39 percent of the vote, down from 43 percent in the previous midterm election in 2014, according to McDonald’s calculations. That’s a four-percentage-point fall from one midterm election to the next, nearly double the average level of decline between presidential cycles since 2000. College-educated whites held steady from 2014 to 2018, at about 34 percent of the vote; nonwhites, meanwhile, surged from 23 percent in 2014 to nearly 27 percent last fall, McDonald found.

These findings are bound to encourage those who believe Democrats should focus on energizing college-educated whites and minorities, who are growing in the electorate (the latter much faster than the former). But the electoral calculation for Democrats may not be that simple. For one thing, working-class whites receded last November only partly because of their waning share of the eligible voting population. They also declined because turnout in 2018, compared with 2014, surged among minorities and college-educated whites, two groups who broke mostly against Trump and the GOP, according to network exit polls. Turnout also increased among working-class whites in comparison with the previous midterm, but not as much.

If Trump mobilizes enough of his white working-class base to narrow that turnout gap in 2020, those voters may recover somewhat as a share of the total vote. Tellingly, McDonald calculates that eligible nonvoters in 2018 split exactly in half—between whites without a college degree on one side, and minorities and college-educated whites combined on the other. That leaves essentially identical pools of nonvoters for each side to target next year.

“When we get to 2020, it does seem like Trump has a little bit of opportunity for upward movement in his core constituency,” McDonald says. “But on the other side of that, we’re likely going to see much higher levels of turnout among the Democratic coalition, younger people and persons of color, compared to 2016.”

The bigger question for Democrats is geographic. The long-term erosion of blue-collar whites as a share of the national vote is unmistakable and irreversible. That trend has ominous long-term implications for a GOP that is relying more heavily than ever on squeezing greater advantage from that shrinking group. But those white voters are disproportionately represented in the pivotal Rust Belt battlegrounds of Pennsylvania, Michigan, and Wisconsin (as well as in Ohio and Iowa, which have trended further away from Democrats). Democrats wouldn’t need to focus as obsessively on those states, and on courting their large working-class white populations, if they could tip some of the diverse and growing Sun Belt states where those whites are a smaller share of the vote, such as North Carolina, Florida, and Georgia, much less Texas. (Arizona, probably the top new Sun Belt target for Democrats in 2020, actually houses an elevated number of non-college-educated whites because it attracts so many white retirees.) But until Democrats can reliably flip some of those Sun Belt states, they can’t downplay the Rust Belt in presidential contests.

Yet even a geographic concentration on the Rust Belt doesn’t necessarily require a demographic focus on blue-collar whites. Democrats could certainly win back Pennsylvania in 2020, and likely Michigan too, without appreciable gains among working-class whites if they’re able to increase turnout among minorities and improve their margins among white-collar white voters. But that’s a thin path. And it would be tougher to win Wisconsin with that approach. Non-college-educated whites make up more of the vote there than in Pennsylvania and Michigan.

In Senate and gubernatorial races across those three key states in 2018—as well as in House races in Pennsylvania and Michigan—Democratic candidates did, in fact, regain ground with blue-collar whites compared with Hillary Clinton’s performance in 2016. They did so largely by running populist campaigns that stressed their determination to preserve the Affordable Care Act, particularly its protections for patients with preexisting medical conditions. Charlie Kelly, who conducted extensive research on blue-collar voters in 2018 as the executive director of House Majority PAC, a Democratic super PAC, says Trump has left himself vulnerable in 2020 by doubling down on his promises to repeal the ACA if reelected. And Kelly argues the president opened a new front by proposing to cut Medicare in his latest federal budget. “That’s a one-two combo that he can’t recover from,” Kelly says. “The idea that Trump has this monopoly on working families is wrong.”

Every potential Democratic presidential nominee will wield those arguments against Trump next year. The implicit question Biden’s candidacy raises is whether more white working-class voters will respond if they hear that case from an older white man with a blue-collar pedigree than from a female, African American, Latino, more progressive, or younger white nominee. Given all of Biden’s other limitations and challenges in a changing party, he’s most likely to win the nomination if a critical mass of Democratic-primary voters believes the answer is yes.

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