Inspired by Brandon Morse’s simple-minded posts at RedState.

If you live in a State where there’s little or no doubt as to which candidate will prevail, your vote doesn’t matter. Your vote for a third-party candidate may make you feel good, but it almost certainly won’t affect the outcome of the election. In fact, a lot of such votes probably won’t affect the outcome of the election. So cast that third-party vote and make your day.

But if you live in a State where the race is likely to be tight, it may matter — especially if there are enough voters who choose to withhold their votes from Trump or Clinton. It mattered in 2000, for example, when the votes cast in for Nader in Florida would have given that State to Gore, who was probably the second choice of most pro-Nader voters.

Consider a voter with a plausible set preferences who lives in a “battleground” State:

1. You’re a fiscal and social conservative, and you usually vote Republican but can’t stand Trump. Protest votes for a third-party candidate (probably Gary Johnson) will mean fewer votes for Trump, and therefore a boost for Clinton. So protest votes for Johnson (vice Trump) will help Clinton, who cannot possibly be more conservative than Trump on fiscal or social issues.
2. You’re a fiscal and social liberal, and you usually vote Democrat but can’t stand Clinton. Protest votes for a third-party candidate (probably Jill Stein) will mean fewer votes for Clinton, and therefore a boost for Trump. So protest votes for Stein (vice Clinton) will help Trump, who cannot possibly be more liberal than Clinton on fiscal or social issues.
3. You’re a middle-of-the-roader who usually votes for the Republican or Democrat who most appeals to you, but you can’t stand Trump or Clinton. Regardless of your distaste for Trump and Clinton, you probably consider one of them to be the lesser of two evils on issues of most importance to you. Protest votes for third-party candidates will help the greater of two evils by reducing the vote count of the lesser of two evils.

Generalizing:

1. Only Trump or Clinton will win the election. No one else has a chance of winning.
2. If you’re truly indifferent between Trump and Clinton, it doesn’t matter what you do. You can flip a coin to choose between them; you can flip a coin (or two) and choose among the third-party candidates; or you can abstain from voting for a presidential candidate.
3. But if you’re not truly indifferent between them, if one of them is merely the lesser of two evils, then your vote for someone else (Johnson, Stein, Santa Claus, the Tooth Fairy) means one less vote for the lesser of two evils. In which case, you’re voting against your own interest because you’re giving an edge to the greater of two evils.

Enough said.

Related post: Economists and Voting