Often lost in the flood of reasons that the 2016 election was historic was the choice Americans were being asked to make. The two candidates on the ballot, Donald Trump and Hillary Clinton, were each less favorably viewed than any major-party candidate who had come before them.

The result was that about a fifth of people who actually came out to vote did so despite disliking both Trump and Clinton, according to exit polling that year. Somewhat remarkably, three-quarters of those voters voted for Trump or Clinton anyway.

About half of them voted for Trump. Choosing between candidates they didn’t really like, they seem to have erred on the side of the candidate who was newer to the political scene, someone who, even if they didn’t like him personally, at least hadn’t done things in office that they didn’t like. So while people who liked Clinton but not Trump (about four in 10 voters) overwhelmingly picked her and while people who liked Trump but not Clinton (slightly fewer) picked him, the 18 percent of those who liked neither gave Trump a 17-point advantage.

In the abstract, it’s something of a statistical quirk. In practice, though, it might have given Trump the White House.

Consider the three states where Trump’s narrow margins gave him enough electoral votes to be inaugurated, Michigan, Pennsylvania and Wisconsin. Here’s how the dislike-both vote played out in those states — and how many votes might have resulted. (See the note at the bottom of this article to explain the math.)

Disliked both
Margin for Trump
Vote differential
Statewide margin

These figures are based on exit polling, which means that there’s a pretty decent margin of error built in. Shave a few points off Trump’s margins with those dislike-both voters — 2 points in Michigan or 5 in Pennsylvania — and he suddenly doesn’t have enough votes to carry the states.

Trump’s strategy in 2020, as in 2016, appears to be to do his best to push down his opponent’s popularity and then boost turnout in his own base. A poll from Quinnipiac University released on Wednesday shows that he has a bit of work to do: Former vice president Joe Biden, now the presumptive Democratic nominee, is viewed about as favorably as unfavorably. About the same percentage of people view Trump favorably as view Biden favorably, but far more view Trump unfavorably.

That Quinnipiac poll, though, allows us to again consider the dislike-both vote. Of those who had opinions about both Trump and Biden, about 11 percent already view both unfavorably.

The good news for Biden? That group prefers him by a 32-point margin.

That’s about the same margin that Biden held when we looked at the same number back in December.

As with every other poll result offered seven months before an election, a lot can change. A lot of those people who don’t like either candidate simply might not vote (which is what Trump probably hopes). Views of the candidates can shift. The 15 percent of respondents who didn’t have an opinion on both of the candidates might form one.

But if the 2020 election comes down to people who dislike everyone on the ballot but want to vote for one of them anyway, the data as it stands suggests that Biden is more likely to benefit.

How the dislike-both vote data works: Consider Michigan. There, 4.8 million votes were cast. Twenty percent of that total — the percent who disliked both candidates — is 965,000. Twenty-one percent of that number — the margin for Trump — is 203,000.