The Democrats’ dilemma is how to reconcile the interest of largely married, middle-income suburban homeowners with their rock-solid activist base of city-dwellers, who tend to be renters and childless. Suburbanites, for example, tend to be less interested in public transportation than media people who live in New York City, and more interested in improving the roads they take to work.

To be sure, the pressure on these newly elected suburban Democrats to abandon their new constituents could be intense. Victoria Fierce, one of the leaders of the tech-funded YIMBY pro-density lobby in California, favors relentless densification because it promotes “collectivism”—thinking that also, incidentally, formed urban planning orthodoxy in the late, great Soviet Union. Lily Geismer, an associate professor of history at Claremont McKenna College, thinks suburbanites should be punished for their “hoarding” of everything from their children’s education to the clear skies where big new developments should be erected.

Other progressives see single-family houses as inherently racist, an accusation that increasingly defines the political agenda of the modern left.