Nati Harnik / AP

Donald Trump and Hillary Clinton are on track to capture the Republican and Democratic nominations, despite both losing a majority of their parties’ primaries west of the Mississippi.

In fact, their campaigns have been buoyed by the same Gulf-Atlantic crescent. Both campaigns have won the swoosh of 15 contiguous states from Louisiana and Mississippi, east through Alabama, Florida, and Georgia, and north from South Carolina, North Carolina, Tennessee, Virginia, Maryland, Delaware, Pennsylvania, New York, Connecticut, and Massachusetts. Meanwhile, in nine of the 13 states where Trump has lost, Clinton also lost. Their maps are surprisingly similar.

The fact that the Trump Country resembles Clinton Country can be deceiving. First, they will not compete across this entire swath in the general election; Clinton won’t compete in Alabama, and Trump has no shot at winning Massachusetts. Second, within this yellow band, the candidates have built polar-opposite coalitions. Their ability to carry separate corners of the same states offers lessons for how their electorates will sort themselves in the general; and how the forces behind Trump mania and Clinton support feed off each other.

Clinton has built the sort of coalition that somebody might expect to find in an American city and its nearby suburbs—a mix of old people, rich people, and minorities. She's winning blacks by a wide margin, and Hispanics, too. Her message is one of optimistic incrementalism, as a lifetime politician and Washington veteran who believes that change comes from within the system.

The Trump phenomenon is the opposite in practically every category, both demographic and stylistic. He is strongest, not among minorities and the rich, but rather among the white and uneducated. His most dependable demographic is middle-aged white men who did not go to college. Neither incremental nor optimistic about the country, his style is more like charismatic doomsdayism—“We never win, anymore,” “Make America great again”—which invites supporters to see the president, not as an important actor in a larger play as Clinton emphasizes, but rather like a one-man show.

Within the Gulf-Atlantic crescent that has been equally important for Clinton and Trump, the differences within particular states illuminate just how opposite their coalitions are. In Virginia, Trump lost women, the affluent D.C. suburbs, moderates, voters with a college degree, and households who made more than $50,000. Clinton didn’t just win these groups. She outperformed in them, winning women, suburbanites, moderates, nonwhite college graduates, and voters making more than $100,000 by huge margins. Meanwhile, Trump’s strength is Hillary’s weakness: the performance of authenticity. Among GOP voters in Virginia who want a candidate who “tells it as it is,” Trump bested his closest rival by a whopping 60 percentage points. Meanwhile, among Democratic Virginians seeking a “honest and trustworthy” candidate, Clinton lost by 50 percentage points.

It’s the same story in Florida, where both Clinton and Trump coasted on separate waves. Trump carried the state but lost Latinos and people who would like the next president to "have experience in politics." Meanwhile, Hillary won two-thirds of the Hispanic vote in Florida and 89 percent of voters who prized "the right experience" in a candidate.

The fact that Clinton Country and Trump Country live within the same states speaks both to the diversity of the American experience and, perhaps, to some of diversity’s uglier side-effects. Hillary’s support from black voters is one of the most important elements of her coalition. Trump, while never explicitly seeking the vote of anti-black southerners, is nonetheless winning in all the places one would expect to see a successful candidacy based on racial animus toward black people. His support matches up curiously well with Google heat maps for racist searches and jokes. This doesn’t prove that "most or even many of his supporters are motivated by racial animus,” Nate Cohn of the New York Times reported, but "it is consistent with the possibility that at least some are.” It raises the disconcerting possibility that Clinton and Trump’s successes in the southeast are intertwined: Clinton is winning among blacks and Hispanics who are there, while Trump is winning among whites who wish they weren’t.

Style will be the most visible difference between Clinton and Trump. Speaking on policy, Trump is a dry-erase board, while Clinton is a Talmud portion; his most specific ideas are haphazard doodles while her remarks are often larded with so much marginalia that her footnotes have footnotes. But one should expect the general election to feel like a referendum on everything other than policy—race, culture, and feelings. Clinton and Trump might frequent the same weddings and tax brackets, but they represent competing binaries: not just male versus female, but also white versus non-white, college versus non-college, radical doomsdayism versus optimistic incrementalism. Voters will have a clear choice.

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