The Democrats have been making some significant gains in suburban America. But it's important to remember that suburbia is a vast section of America and should not be thought of as just the suburban outgrowths of our largest and most dynamic cities. There is much, much more to suburbia than that. And once you get away from these more cosmopolitan suburbs, the voters (more white, less educated) and Democratic progress look quite different.
I noted this point in various analyses I conducted of the Obama elections. The differences I discussed at the time between small and medium metros and the largest metros remain very relevant. David Hopkins rehearses some of the current data in a very good New York Times op-ed.
"[Democrats] have not extended [their] success to the suburban communities surrounding smaller cities, which remain predominantly — even increasingly — Republican. The suburbs surrounding Jacksonville, Fla., Indianapolis and Grand Rapids, Mich., for example, provide Republican candidates with more than enough votes to compete in, and often win, statewide elections.
To achieve a durable national majority, Democratic candidates will need to expand their appeal to the less diverse and more culturally conservative electorates of the small-metro suburbs, which remain aligned with the Republican Party even in the era of Donald Trump....
The growing partisan divergence separating large-metro suburbs from those in the rest of the country extends to congressional elections....[I]n the nation’s smaller metro areas, where the share of suburban House seats held by Republicans rose to 71 percent after 2018 from 60 percent after the 1994 election, Republicans continue to thrive. Even last November’s “blue wave” hardly threatened Republican incumbents like Warren Davidson of suburban Cincinnati-Dayton, who won re-election by 33 percentage points; Gary Palmer of suburban Birmingham, Ala., who won by 38 points; or Francis Rooney of suburban Cape Coral, Fla., who won by 25 points....
President Trump’s historically strong performance in a string of smaller and more homogeneous suburbs from greater Scranton, Pa., to greater Des Moines proved pivotal in the 2016 election and could well recur in 2020. Broadening the Democratic tent to bring more of these socially traditionalist small-metro suburbanites into the fold would provide the party with a critical electoral advantage, but such gains will be difficult to achieve in an era of growing cultural warfare."
That's the challenge. We'll see if the Democrats are up to it.