One of the great paradoxes of 2016 is that Republican primary voters in races below the presidential level have mostly repeated the pro-establishment tilt of the 2014-15 primaries, even while picking a presidential nominee who represents a simultaneous rebellion against every faction of elected Republicans at once. Whether by ideology or temperament, there’s very little Donald Trump has in common with the people winning primaries in the GOP this year, often in primaries held on the same day and thus before the same electorate.
Nathaniel Rakich has a deep dive into the numbers to support this:
In those races with an incumbent running for re-election and/or a clear establishment-versus-insurgent tone, I found that the establishment candidate did better in 2016 than 2012 14 times and did worse 17 times. Overall, there is a very frail argument to be made that establishment candidates did fare worse this year, but their average drop—just 1.6 percentage points—is statistically negligible.
Rakich suggests that part of the reason is that we haven’t seen many down-ballot candidates like Trump trying to run this year, and so it’s not shocking that Trump voters are split when choosing between, say, a candidate who sounds like John Kasich and one who sounds like Ted Cruz. Whether such candidates emerge in 2018 and beyond will probably be affected a lot by what happens to Trump himself in November.
Another possible explanation, which should not be underestimated, is the extent to which Trump’s success is as much a feature of his celebrity and long-established brand, more than anything especially ideological. Congressional candidates who haven’t been national TV personalities and household names for three decades are not able to imitate that part of his appeal.
It’s an important question, because unless and until we see other candidates replicate Trump’s success, we shouldn’t assume that his movement is actually going to bring about any sort of permanent change in the GOP’s coalition or platform (at least in terms of addition, rather than just people who are alienated from the party). But if we do see that happen, it won’t be in 2016.