Chris Dillow makes a very good point about the Brexit vote (boldface mine):
There’s something about the post-Brexit autopsies that I’m not entirely happy with. It’s the failure to distinguish between the margin and the infra-margin.
…It’s that we knew months ago that older, poorer and less educated people were anti-EU. And yet Brexit came as a surprise – to betting markets, financial markets and not least to David Cameron.
This paradox warns us that whilst the conditions for a big anti-EU vote were in place – we knew for months that some 40% of voters supported Brexit – what remains unexplained is the surprise.
To put this another way, longstanding anti-EU sentiment was infra-marginal. The question is: what happened at the margin to tip the balance in favour of Brexit?
…What I’m trying to do here is reconcile two different perspectives. On the one hand, Eric says “culture and personality, not material circumstances, separate Leave and Remain voters. This is not a class conflict so much as a values divide.” And Rick says “the left-behind who voted for Brexit last week were left behind a long time ago.” These are statements about the infra-margin. But when I say that austerity and inequality – as cleverly exploited by Vote Leave – contributed to the Brexit vote, I’m claiming these things mattered at the margin.
Elections are won at the margins. Increases in turnout–which is to say, getting voters who will either vote Democratic or stay home–matter. While Clinton will most likely beat Trump, Democrats (as opposed to the Clintons and their hangers-on) need House and Senate Democrats. I worry that Democrats are too focused on the presidential race at the expense of the down ballot races. And I’m not the only one either.