Tarrant County, Texas, hasn't supported a Democrat for president since 1964 — that is, until 2020. The state's most reliably red urban county swung in Joe Biden's favor by just 1,500 votes out of more than 800,000 cast, but that's all it took. The county's big city of Fort Worth is now blue like its neighboring Dallas, and Biden expanded Hillary Clinton's 2016 vote share in the once-ruby red suburbs of northeast Tarrant. Even nearby Arlington went for Biden; it's a city where I lived the first decade and a half of my life without ever knowingly meeting a Democrat, and whose once-empty prairies are now home to more people than Cleveland or New Orleans.

Driving north from Tarrant, you won't see a blue county until you've passed the Red River and onward for hundreds of rural miles to Topeka, Kan., where Biden won by a margin of just 0.5 percent. Even heading south from the sprawling metroplex of Dallas-Fort Worth, the next Democratic base is in Austin, some 170 miles away as the crow flies, or roughly the distance from New York City to Boston. Rural Republicans meeting Democratic density — this is Texas in a nutshell, and it's a window into the rest of the country's polarized politics. So too for the Lone Star State's surprises, like the heavily Hispanic border counties swinging dramatically toward Donald Trump, just as Tarrant County's most diverse precincts did.

America's urban-rural partisan divide is likely the greatest it's ever been, with cities and suburbs moving farther left in 2020 as rural areas swung right. While votes are still being counted, it seems that Joe Biden won America's 10 largest cities, besting Clinton's count of nine. Seventy-one percent of America's 436 most urbanized counties — those in metro areas of more than a million in population — increased their support for Democrats, while Trump expanded on his already large winning margins in 54 percent of rural counties. Even in urban areas that Trump won, such as Colorado Springs, Colo., he lost ground. Across the electoral landscape, high-income and well-educated suburbs pulled farther left, while less-dense suburbs became less Republican. Winning these crucial suburbs handed Biden not just swing states like Wisconsin and Michigan but likely the presidency.

As has been becoming clearer for years, polarization is not simply a phenomenon of ideology now, but also one of geography, economy and culture. Proximity to a Whole Foods, as well as other upmarket brands such as Lululemon, continues to be a reliable predictor of Democratic victory, just as proximity to a Cracker Barrel is for Republicans. This year at least 13 more "Whole Foods counties" swung from red to blue, reflecting increased support from the same well-off and educated voters upmarket retailers covet, and flipping Arizona along the way. In all, 477 Biden-voting counties account for 70 percent of GDP, while Trump's 2,497 winning counties produce 29 percent.

The power of the urban vote was also evident in statewide referenda, but often in unpredictable ways. In Florida, voters in every major metro area backed hiking the state's minimum wage to $15 an hour, even as the state's 29 electoral votes went for Trump. Meanwhile, California voters overwhelmingly pulled the lever for Biden while also rejecting regulations on the gig economy, an expansion of rent control and a proposal to end the state's ban on the use of race and gender preferences for public institutions. Results from California's ballot initiatives resemble a sea of red dotted with islands of coastal blue, with diverse inland population centers like the heavily Hispanic Riverside rejecting progressive measures.

And it is here, among nonwhite voters, where the blue urban wall revealed its cracks in 2020. In Miami-Dade County and along the Texas-Mexico border, Trump's vote share rose by an astonishing 20 percent or more from 2016, thanks to support from Latinos of Cuban and Mexican origin, respectively. In exit polls, these working-class urban voters were more focused on the state of the economy than on COVID-19, and were often more socially conservative than the typical Democrat. While small Zapata County going Republican for the first time in a century may not move the needle in Texas, Trump improving on his 2016 performance in El Paso, or making breakthroughs in Harris County's minority precincts in the center and south of Houston, just might. In California, it wasn't just Latino voters making their presence known on ballot initiatives: San Francisco's winning referendum to raise property taxes faced decided opposition from Asian voters on the city's outskirts.

These disparate election results suggest that those on the right would do well to court an urban coalition of ethnically diverse, often working-class voters. And while the overall partisan divide by population density first became clear two decades ago with the 2000 election of George W. Bush, and its roots likely go back even further to the Industrial Revolution's advent of an urban working class, there is nothing in politics that must be set in stone. Amid the clusters of dense blue against a rural red backdrop, there are more colors to behold.