Judging by past experience, this intra-party tension will be resolved in favor of the interests of tax-sensitive suburbanites. Democrats will surely make symbolic concessions to the priorities of socialists and environmentalists, who will continue to play an essential role in marketing centrist candidates to the young and the intelligentsia. But they seem most likely to rely on negative partisanship, which is to say deep-seated opposition to the Republican Party, to keep their coalition intact.

As HENRYs cement their central role in the Democratic Party, we can expect Republicans to be less solicitous of their wants and needs, and to go hunting for new voting blocs that might be more receptive to conservative cultural appeals. Doing so will be exceptionally difficult in the near term, as President Trump is an intensely polarizing figure about whom most voters and potential voters have long since made up their mind. For now, as I argued in the immediate aftermath of the midterms, the best Republicans can hope for is to win back some of the Obama-Trump voters of the industrial Midwest, many of whom have since returned to the Democratic fold.

Looking further out, though, Republicans will have no choice but to attract a far larger universe of working-class voters to address the upper-middle-class exodus. Regardless of the outcome of the next presidential election, younger members of the party need to start thinking about the post-Trump landscape, and what it will take to expand the Republican coalition. The loss of HENRYs could, in theory, free Republicans to pursue policies that might cut against the interests of affluent voters while serving the interests of other voters with more modest incomes. Again, skepticism is warranted as to whether the incumbent GOP political class is capable of adapting to this new political landscape. But as Trump demonstrated in his 2016 presidential campaign, political entrepreneurs are always lying in wait to exploit unrealized opportunities.

David Frum: The Republican party needs to embrace liberalism

How should newly elected Republican senators position themselves for the political battles to come? How should Republican lawmakers reckon with the fact that the conservative bromides that served them so well in the days of Tom DeLay now fall on deaf ears? The short answer is that they need to recognize that Democrats have a growing advantage in economic policy, which is why they’ve made such significant gains in previously safe Republican districts . Short of a large and very visible shift to the center along these lines, Republicans might be shut out of winning the House for some years to come.