Leading up to this past Tuesday’s election, Tim Hugo, the last Republican state legislator representing a district in the suburbs of northern Virginia, did his best to distance himself from the toxicity of Donald Trump and the G.O.P. His Twitter profile didn’t mention the Party—neither did the biography on his campaign Web site or his campaign posters, which were blue rather than red. The Washington Post reported that when Hugo was cornered by reporters at a candidates’ forum and asked repeatedly what role Trump was playing in his race, he replied, six times, “I focus on the local issues.”

This evasive strategy wasn’t enough to save Hugo, who has served in the Virginia House of Delegates since 2002. (He was initially elected with more than seventy per cent of the vote.) His Democratic opponent, Dan Helmer, a Rhodes Scholar and military veteran, defeated him by almost five percentage points. When the next legislative session starts, the affluent region south of Washington, D.C., which for decades was a bastion of Republicanism, won’t have a single Republican representative. Looking at Virginia as a whole, all three branches of government—the governorship, the House of Delegates, and the state Senate—will be under Democratic control for the first time since 1993.

The shift from red to blue in places like Fairfax County started well before Trump arrived on the scene, of course. It is largely driven by demographic factors, including an influx of new voters who tend to be younger, highly educated, and more ethnically diverse. But the takeaway from Tuesday’s election confirms what we saw in last year’s midterms: Trump is accelerating these long-term trends and spreading poison for Republican candidates in the suburbs.

The pattern extends beyond Virginia. In Pennsylvania, which is crucial to Trump’s reëlection hopes, the Democrats took control of local governments in three leafy but populous counties north and west of Philadelphia: Bucks County, Chester County, and Delaware County. “There continues to be bloodletting and further erosion of suburban voters from the GOP,” Charlie Dent, a veteran Pennsylvania Republican who retired from a U.S. House seat in Lehigh Valley last year, told the Philadelphia Inquirer. “I just don’t know how Republicans will be able to offset the losses in suburban and exurban communities with increasing tallies from rural voters.”

Republican candidates did make some progress in western parts of the state, which are more rural and Trump-friendly. In fact, the Party gained control of six county commissions. But as the Daily Kos’s Stephen Wolf pointed out, the five Pennsylvania counties that the Democrats flipped have more than twice as many residents as the six that the Republicans turned. Ultimately, politics is a numbers game, and the larger populations tend to be in the suburbs, where the Republicans are struggling badly.

Dent wasn’t the only Republican to acknowledge this fact. Senator Pat Toomey, who won reëlection in 2016, and who is now the only Republican holding a statewide office in Pennsylvania, conceded that the results from the Philly suburbs were “extremely disappointing.” The fiercely conservative editorial page of the Wall Street Journal took a sober look at the national picture, which included the narrow defeat of Matt Bevin, the Republican governor of Kentucky, who had associated himself closely with Trump. “Democrats showed again that they are highly motivated in the Trump era,” the Journal’s editorial said. “This turnout trend has now continued for three Novembers, and Republicans who try to explain it away are fooling themselves.”

Looking ahead to 2020, the editorial concluded, “The fair judgment a year from Election Day in 2020 is that Mr. Trump is highly vulnerable in his bid for a second term.” That seems incontestable. Arguably, however, Republican Party leaders should be even more worried than the President. As I wrote earlier in the week, given the skewed geographical distribution of Trump voters and potential Trump voters, there is still a chance that he could pull another inside straight in the Electoral College to win a second term. That’s all he desires, of course. But the Republican Party was founded in 1854, and, if it wants to survive for another hundred and sixty-five years, it needs to align itself with some growing parts of the electorate rather than turning into an embittered rump party for rural working-class whites.

In the long term, such a path leads to oblivion, which the Republican National Committee itself acknowledged in a 2013 report that is now presumably gathering mold somewhere at Republican H.Q. In the shorter term, the Trump path will only lead to more misery for G.O.P. candidates in suburban districts—particularly as Democrats in states like Virginia and Pennsylvania redraw electoral maps to undo years of Republican gerrymandering, or perhaps even to administer to the Republicans some of their own foul medicine.

So when will endangered Republicans summon up some courage and challenge their rogue President? For at least two reasons, the answer is: not until the voters repudiate him first.

Most elected Republicans live in mortal fear of Trump’s Twitter feed, which he turns on anyone from his own party who dares to criticize him. (Exhibit A: Paul Ryan, the former Speaker of the House, who told the author Tim Alberta that Trump “didn’t know anything about government,” only to find himself dismissed by the President as an incompetent loser.) And Republican politicians are equally frightened of Trump’s supporters, who have seized control of the local Party machinery in many parts of the country and react just as ruthlessly as he does to any perceived disloyalty. (Exhibit B: Francis Rooney, a congressman from southwest Florida. Last month, Rooney suggested that he might be open to the possibility of impeaching Trump. A few days later, after being targeted by local activists, he announced that he was retiring at the end of the term.)

As November, 2020, approaches, many Republicans representing suburban districts may follow Tim Hugo’s example and try to localize their races, with hopes of getting a different result. A few may even pray that Trump loses both the Presidency and his stranglehold on the G.O.P., but they will keep those invocations to themselves. Of that, we can be virtually certain.