One of the Karl Roves of the world, Karl Rove, concedes that Republicans have immediate and long-term challenges in Texas. “We’ve got to do better with the Latino community, but the big problem for Republicans in Texas isn’t Latinos—it’s urbanization,” says the former aide to President George W. Bush and regular contributor to these pages. Six of the 25 largest U.S. cities are in Texas; Dallas and Houston are the fourth- and fifth-largest metropolitan areas in the country, respectively. And it is in and around these cities that Republicans are falling behind. Houston and San Antonio have been strongly Democratic for a generation, and their suburbs are trending that way, too. When Fort Worth went for Mr. O’Rourke over Mr. Cruz, that left the Panhandle outpost of Lubbock, population 255,000, as the largest reliably Republican city in the state.

“Republicans are going to lose incumbent seats on election night, absolutely,” says Konni Burton, a tea-party leader who lost her Fort Worth-area state Senate seat to a Democrat in 2018. She thinks Republicans may keep the Texas House but warns that the GOP faces headwinds in increasingly affluent and educated areas such as the one she represented. “They’re put off by Trump,” she says of suburbanites. “The question is whether they’ll come back once he’s gone.” She isn’t sure but says recent Republican attempts at moderation have failed to win over new voters, succeeding only in enraging the base.

Democrats are cautiously optimistic that they can flip nine seats in Texas—but maybe only nine. Republicans trust that their low-key but fruitful registration efforts and a sophisticated get-out-the-vote operation will see them through. “Biden Takes Texas” would be a great headline for Democrats, but a blue wave crashing into Austin would be the more telling development, and the more fearful one for Republicans with an eye to the long term.