Continuing on a theme, let's talk for a bit about the mechanics of legislative elections, and why Senate elections are more susceptible to minor, weird effects, like Trump, than House elections, creating the possibility of the chamber switching hands because one party nominated a... well... Trump.
First, in order for a seat to be in play, the partisan balance has to be relatively even. You've probably heard that all of the House seats have been "gerrymandered" to be non-competitive. Bullshit. Usually, around 25% of House districts have the two presidential candidates separated by less than ten points in the two party vote. Anyone who wants a citation can use my essay in Ellis & Nelson's Debating Reform. Regardless, there are frequently enough evenly balanced states to flip the chamber. But, it depends on which states are up in any given year. This year, some of the battlegrounds are tough for Republicans. Why? 2016. That means all of the seats they won in 2010, with a big wave election are up. They won, in a sense, too many seats because of the unique circumstances of 2010. Those are hard to keep without those circumstances. Now, things start to revert.
Next, in order for a seat to be in play, you need either an open seat (rare), or for the incumbent to be challenged by someone who isn't a nutjob. Now, here's a plug for some research that really should have been published, but as far as I could tell, never got out, so here's at least something. A colleague from grad school did a great dissertation on competitive primaries. Casey Dominguez, now at University of San Diego. She asked candidates to fill out a survey on why they ran, etc. My personal favorite, who became a running joke among our cohort, kindly filled out the survey, and returned it. With a large feather. And a pad lock. And no explanation.
Now and for all time, he shall be known as "lock and feather guy." Anonymity and all, he can be known as nothing else anyway, but great story, right?
Lock and feather guy lost. I know, you're shocked. Here's something else that will shock you. Lock and feather guy had never held elected office before.
Those two facts are related. And they are related to the... weirdness.
Most challengers, if not as weird as lock and feather guy, are, shall we say, on that spectrum. And they have never held elected office before. And they lose.
And this confirms a key lesson that we all learned long ago from Gary C. Jacobson, who taught us everything we know about congressional elections with The Politics of Congressional Elections.
And you know what? Senate incumbents are more likely to face strong challengers than House incumbents. Why? More desirable seat. That leads to a closer match, which makes things easier to sway with weird stuff.
Senate elections are closer than House elections. That makes minor things more likely to switch the outcome. And here comes Donald...