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Democrats turned over their convention keynote speech last night to a split-screen array of 17 diverse young leaders one day after news leaked that Republicans had invited to speak at their convention the white suburban couple who brandished guns at a multiracial group of Black Lives Matter protesters outside their St. Louis home in June. Even with all else that has happened during Donald Trump’s tumultuous presidency, there may not be much else you need to know about the lines dividing America in the 2020 presidential election.

Despite a pandemic that has killed more than 170,000 Americans and cratered the economy, the latest surveys show Trump maintaining strong support among the white voters most uneasy about the demographic and cultural changes remaking America, particularly those who are evangelical Christians, live in rural areas, or lack a college degree. And despite a Democratic nominee who stirs only modest enthusiasm among many key party constituencies, those same polls show Joe Biden amassing big advantages among the groups most comfortable with those changes: young people, racial minorities, secular Americans, and college-educated white Americans.

This division of the electorate leaves Biden holding a steady and substantial lead in national polling over Trump that matches or slightly exceeds the Democrats’ 8-percentage-point edge in the total national vote for the House of Representatives in 2018. But the uneven distribution of these contrasting constituencies across the battleground states means that Democrats will likely remain nervous through Election Day about their ability to win the Electoral College, even if Biden maintains a healthy lead in the popular vote.

Last night’s proceedings were effectively a tribute to America’s growing diversity. The energetic, quick-cut keynote speech included multiple speakers who were Latino, Black, Asian American, Native American, and LGBTQ, not to mention several women. The brilliantly reimagined convention roll call reinforced the point, with brief testimonials—some somber, others endearingly goofy—from another diverse roster of speakers in every state and territory, a change that drew rave reviews on Twitter and TV news. Some Democratic activists complained that organizers had allocated too much of the event’s limited time to Republicans and too little to nonwhite progressive leaders such as Stacey Abrams and Alexandria Ocasio-Cortez. But average viewers probably absorbed a very different image: On a day when Trump delivered an incendiary speech in Yuma, Arizona, touting his border wall and even reprising the language from his 2015 campaign announcement about immigrants as “murderers” and “rapists,” Democrats offered the 21st-century version of a Norman Rockwell painting.

That contrast testifies to the depth and the intractability of the modern American divide. Even as Democrats gather to nominate “Scranton Joe” Biden, whose supporters have long touted his ability to recapture working-class white voters, many indications suggest 2020 could cleave the electorate more deeply than ever before, with a diverse, more and more educated, culturally cosmopolitan, metropolitan-based “coalition of transformation” on the Democratic side and a preponderantly white, heavily blue-collar, Christian, nonurban “coalition of restoration” on the Republican side.

The stark reality of that separation would test the bridge-building capacity of any president. Through the 2020s, tension is likely to grow between the diverse communities on display this week and the white constituencies that Trump is trying to mobilize by describing the BLM movement as a “symbol of hate” and by warning “The Suburban Housewives of America” that Biden will “destroy” the suburbs by allowing more low-income housing. If a majority of working-class and Christian white America responds to Trump’s openly racist appeals when they represent a little more than 40 percent of the population, as they do today, there’s little to suggest they will be less responsive to such arguments as their share falls into the 30s, as it will inexorably within a few years.

The flurry of preconvention surveys shows a few unique twists to the 2020 matchup between Trump and Biden, such as Biden’s potential to run better among seniors than any Democrat since Al Gore in 2000. But mostly, the polling shows even further acceleration in the trends that have reshaped—and separated—the two parties’ coalitions since the razor-thin election of 2000.

Despite all of the controversies that have battered Trump’s presidency, especially his erratic response to the coronavirus pandemic, these polls show him retaining very solid support among his core groups. Surveys released since August 11 by Monmouth University, CNN, NBC/The Wall Street Journal, and ABC/The Washington Post all found Trump attracting from 57 to 60 percent of white voters without a college education. The latest NPR/PBS NewsHour/Marist survey put his number slightly lower at 55 percent, while the most recent Pew Research Center poll put him higher, at 64 percent. Trump’s margin over Biden on these measures ranges from just more than 20 percentage points to about 30 points.

That’s not as formidable as Trump’s advantage in 2016, when various data sources measuring voting behavior generally put his lead among non-college-educated white voters even higher. And polls in the Rust Belt battleground states, such as the latest Marquette University Law School survey, show Biden performing better among those voters there than he has nationally. Trump’s small overall decline, especially in key battlegrounds, might be enough to deny him a second term by flipping back the three “blue wall” states he won narrowly last time: Michigan, Pennsylvania, and Wisconsin.

But Trump’s ability to hold on to about three-fifths of non-college-educated white voters nonetheless testifies to the power of the cultural and racial attitudes that bond them to him. Even non-college-educated white women—though clearly less supportive now than in 2016—still give Trump a clear majority of their votes in all of the recent national surveys for which those data were available. (Biden leads among those women in Wisconsin, the Marquette poll found.) In the South, Trump continues to amass towering margins among white voters without a college degree: He’s at 70 percent or more among them in recent polls in North Carolina and Georgia, and nearly that high in Texas. Polls likewise show that Trump is maintaining support from about three-fourths (NBC/WSJ) to four-fifths (Pew) of white evangelical Christians. With rural voters, the Pew, NBC/WSJ, and ABC/Post polls all put him at from 55 to 60 percent support.

Those numbers in rural communities would also constitute slight declines from 2016, and that threatens Trump, given how narrowly he won last time. But all of these results signal how many white Americans remain responsive to Trump’s underlying argument that a victory for the diverse Democratic coalition on display this week would irreversibly transform the nation into something they consider alien and unacceptable. It is that audience Trump explicitly targets when he declares, as he did in his Yuma speech, that if Biden wins, “our country will not be the country that we know.” (Trump also nodded to such voters last night when he praised the victory in a Republican House primary of the extremist anti-Muslim candidate Laura Loomer, one week after he congratulated a follower of the QAnon conspiracy theory who won a GOP primary in Georgia.)

But the polls also make clear that Trump’s party is paying a heavy price for his decision to so closely align Republicans with the priorities and resentments of the constituencies most uneasy with what America is becoming. The numbers vary, but Trump rarely attracts even one-third of adults younger than 35. Trump lost minority voters by more than 50 percentage points in 2016 and usually draws support from only about one-fourth of them now. (Still, some Democrats worry he might slightly nudge up his support from 2016 among Black and Latino men.) Among the growing group of adults unaffiliated with any religious tradition, Pew found Biden winning more than seven in 10 voters.

The sharpest movement away from the GOP in the Trump era has come among well-educated white Americans. Until 2016, no Democrat had ever won white voters with a college degree in either the media exit polls (tracing back to the 1970s), or the University of Michigan’s American National Election Studies surveys (extending back to 1952). In 2016, the exit polls showed Trump narrowly carrying these voters, but some other data sources, including the ANES, gave Clinton the edge. Two years later, the midterm exit polls for House races showed Democrats winning college-educated white women comfortably, but losing the men narrowly, putting the party at 53 percent with college-educated white voters overall.

Most of the new polls over the past two weeks show Biden with much higher support: From 57 to 61 percent of college-educated white voters support him. Those numbers are unprecedented—as is Biden’s lead among both college-educated white men and women. As recently as the GOP midterm sweeps of 2010 and 2014, Democrats won only about one-third of college-educated white men. Given these patterns, the tendency of Democrats since 2000 to run better among white Americans with a college education than those without one—what I’ve called “the class inversion”—is on track to reach its all-time peak.

Trump’s appeals to cultural conservatives have compounded his difficulties with those well-educated white voters, GOP strategists I’ve spoken with acknowledge. Tom Davis, a former Republican representative from suburban northern Virginia, who chaired the National Republican Congressional Committee during his years in the House, told me there’s an audience of suburban white voters “who are disgusted” with the violence during recent protests and the calls to defund the police. But overall, he believes, Trump’s arguments are backfiring. “They’re overplaying this with a blunt force that is not the way to appeal to college-educated people that like to feel they are open-minded and open to diversity,” said Davis, now a partner at the Washington, D.C., law firm Holland & Knight.

Nick Gourevitch, a Democratic pollster, agrees. “White-grievance politics reinforces the battle lines of the last three years,” he told me. Which side that helps, he said, depends on whether you believe those battle lines are good or bad for Trump. “I’ve always felt that those battle lines are not good for him and that he doesn’t win with them,” Gourevitch continued. “I don’t think there is any real evidence that this is gaining him anybody other than the people who like him to begin with.”

New data provided to me by Pew help fill in the long-term risk in Trump’s strategy. From 2004—the last time a Republican presidential candidate won the popular vote—through 2016, the GOP’s core group of non-college-educated white voters tumbled from 52 to 42 percent of the total national vote. Over that period, those same voters declined as a share of the electorate across a broad group of battleground states: by at least 9 percentage points in the prototypical Midwest states of Wisconsin, Minnesota, Michigan, and Iowa; by 8 points in Ohio; and by 7 in Pennsylvania. They fell by 8 percentage points or more in the current and emerging Sun Belt battlegrounds of Georgia, Florida, Arizona, and North Carolina; as well as by 9 points in Virginia, which has become safely Democratic since 2004. In Texas, they declined by 6 points.

In each state, the share of either college-educated white voters or people of color grew to fill in the gaps. If these trends continue this year, Trump faces the likelihood that his base of non-college-educated white Americans will shrink to about 40 percent of the total vote in November—and maybe even less if Black turnout recovers from its sharp decline in 2016.

In a parallel progression, the share of Americans who identify as white and Christian is decreasing, while those who don’t identify with any religious tradition is growing. A generational flip is coming too: By 2024, Americans born after 1981 will significantly outvote those born before 1964.

All of these transitions will produce an American electorate that looks more like the cast at this week’s Democratic convention than the likely lineup for Trump next week. Many obstacles still inhibit that emerging America from consolidating political power, including lower turnout among younger and nonwhite voters, excess concentration of Democratic support in big metro areas, and solidifying Republican dominance of rural states favored in the Senate and the Electoral College.

More immediate problems also threaten the new Democratic coalition. Blue-collar white voters still significantly exceed their national share of the vote in the big Rust Belt battlegrounds that Democrats must win until they demonstrate that they can reliably flip more diverse Sun Belt states. Widespread questions remain over whether Biden, even after adding Kamala Harris as his running mate, can excite greater turnout than Hillary Clinton did among younger voters, especially nonwhite ones. And this year, many Democratic election strategists are grappling with an unprecedented concern: fear that the party’s heavy reliance on urban and suburban voters could leave it “immensely vulnerable,” as one put it, to Trump’s efforts to suppress the vote—for instance, by disabling mail service in a handful of big cities around Election Day.

But Trump has committed the GOP to a strategy of squeezing bigger margins from a shrinking share of the electorate, while systematically alienating the growing groups that Democrats are highlighting this week. He may still be able to squeeze out another Electoral College victory even if he almost certainly loses the popular vote. But even that pathway is not realistic, strategists on both sides acknowledge, unless he can significantly cut his current popular-vote deficit. “Donald Trump basically drew an inside straight in 2016,” says the longtime Republican pollster Whit Ayres. “The question is whether he can draw an inside straight two hands in a row.”

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