Nonvoters Are a Source of Hope for Democrats. But Maybe a False Hope.

What about whites without a degree, the president’s base? Mr. Trump has a 25-point lead over Mr. Biden in this group if they have voted in one of the last two elections, 59 percent to 34 percent. Those who stayed home, however, back Mr. Trump by a smaller margin of 53 percent to 36 percent. The pattern holds after controlling for age.

Taken together, the figures imply that a large portion of nonvoters sit out because they do not neatly line up with either party. This fact tends to limit the opportunity available to both parties, but over all it tends to diminish the Democratic advantage that would seem to exist based on their demographics alone.

One exception to this general pattern is among Hispanic nonvoters, who tend to be just as Democratic as their voting counterparts, or even more so.

Over all, Mr. Biden led among nonvoting Latinos, 64 percent to 24 percent, compared with a 63-30 lead among those who had voted in either 2018 or 2016. The sample of nonvoting Hispanic voters is fairly small, but the finding is consistent with data previously analyzed by The Upshot.

As a result, Democrats enjoyed a far larger edge among nonvoters in our poll of Arizona, where 33 percent of registered nonvoters were Hispanic, than elsewhere in the battlegrounds. Mr. Biden led among nonvoters in Arizona, 55 percent to 37 percent, thanks to a 74-12 lead among Hispanic in that group. In the rest of the battlegrounds, Mr. Biden had only a one-point lead among nonvoters.

The relative Democratic strength among Hispanic voters may also mean that nonvoters nationwide may be more Democratic than nonvoters in the battlegrounds, since nonvoters nationwide are likelier to be Hispanic. It may add further intrigue to speculation about Democratic prospects in Texas, where nonvoters are even more diverse than they are in Arizona.

Of course, Democrats — or Republicans and the president — could benefit from higher turnout if it drew disproportionately from their pool of voters. The Times/Siena data confirms this has happened before.