Many of the questions political observers asked before this election revolved around the assumption that it would be a big year for ticket-splitting. Early on, there was a lot of talk about former Bernie Sanders voters going for third- and fourth-party presidential candidates while returning to the Democratic column down-ballot. And of course there was even more talk — encouraged by figures ranging from Hilary Clinton to (indirectly but distinctly) Paul Ryan — that Republicans who could not abide Donald Trump would vote for Clinton, Gary Johnson, Evan McMullin, or just leave the presidential line blank, while putting on the party harness and voting loyally for GOP candidates for Congress and other offices. Sure, ticket-splitting had been on the decline for a long time, and yes, partisan and ideological polarization, driven by Republican extremism, had become the dominant political phenomena of our era. But it seemed like the kind of insane election year that could upset the usual calculations.
In the end, though, partisanship trumped — if you will excuse the expression — everything. As Harry Enten explains at FiveThirtyEight, ticket-splitting actually declined from prior elections, particularly with respect to the presidential and Senate races:
[T]his is the first time that all the states (with Senate races on the ballot) have voted for the same party in both the presidential and Senate races. Senators were first popularly elected in 1914, and the next presidential election took place two years later, in 1916. So that’s 100 years and 26 presidential election cycles in all. You’d have to go back to 1920 to come even close to seeing anything like it.
Enten goes on to show that in states where both Trump and Republican Senate candidates won, the average variation in their votes was just one measly point. Even more revealing is the fact that it did not seem to matter whether the Senate candidate in question endorsed, rejected, or ignored Donald Trump. Enough voters climbed up on the pachyderm and stayed there to give Republicans their very close winning night (even while, lest we forget and start talking about Republican mandates, they lost the presidential popular vote, two net Senate seats, and at least six net House seats).
Does this mean in the end, despite all of our assumptions to the contrary, that it did not matter who was running at the top of the two tickets? That’s hard to say, though all the straight-ticket voting should give pause to Democrats who assume Bernie Sanders or Joe Biden would have won easily, and to Republicans who view the results as a vindication of Trump’s crude and savage message. Exit polls indicate an awful lot of Republicans had a dim opinion of Trump and voted for him anyway. Maybe that’s because they disliked Hillary Clinton even more. But in most cases the simplest explanation is plain partisanship.
If partisan polarization is actually increasing, as Enten notes, this could be bad news for Democratic prospects for ever controlling the Senate again, since more states regularly vote Republican, making ticket-splitting essential for Democrats. We may find out how bad it is in 2018, when nine Democratic senators from states carried by Trump on Tuesday will be up for reelection. Usually there’s something of an anti–White House trend in midterms. Senate Democrats will sure need it.