If recent cycles are any evidence, we can expect roughly 130 million people to vote in this election. They will constitute about 60% of eligible voters. In off years, when there is no presidential contest, roughly 40% of eligible voters vote. Therefore simple math tells us that 43 million or so of those expected to vote this year are what Donald Trump would call “low energy” voters, people who cannot be counted on to turn out in off years. Experience also teaches us that Republicans are more likely than Democrats to vote in off-year elections. That is why the Democrats keep winning the White House but nevertheless lose the House big time [leaving aside gerrymandering and residential clustering]. Let us take a flying guess, powered by nothing but unfettered imagination, and assume therefore that 23 or 24 million of those 43 million low energy fair weather voters are Democrats and the remaining 19 or 20 million are Republicans.
Conventional wisdom among professional bean counters has it that House incumbents can hope to run six or eight points in their district ahead of a losing presidential candidate of their party, but that they are not likely to survive a “wave” election in which the presidential candidate of the opposing party wins by as much as ten percentage points. This far out, it is difficult to predict, but the polls suggest that this year is shaping up as a 5-7 or 6-8 point victory for Clinton, more than enough for a big Electoral College win but not a wave that could be expected to win back the House.
HOWEVER: Suppose the polls are misleading, in the following way. There might be a rather large group of Republican voters who find Trump unacceptably distasteful but would never consider voting for Clinton. Asked their preference now by a pollster, they might grimace and select Gary Johnson [the Libertarian Party candidate] or simply say “don’t know.” When polled about Senate or House races, they will choose the Republican. If these folks are reliable off-year voters, then they will show up even if they hate their presidential choices and, while they are in the voting booth, they will vote for down-ticket Republican candidates. But some of them will be “low energy” voters who may not bother to turn out this year if they are sufficiently turned off by Trump, and their votes will be lost to the down ballot Republican candidates.
QUESTION: Will there be enough of these lost votes to turn a 5-7 or 6-8 point Clinton win into a down ballot wave that wins the House back for the Democrats? We had better hope so, because the fate of all the progressive legislation we yearn for depends on it.