The voters likely to decide the Biden-Trump rematch don’t participate in most elections. They are irregular voters who tend to skip primaries and midterm elections but do often turn out for the country’s highest-profile campaign — a presidential election.

Nate Cohn, The Times’s chief political analyst, explained this phenomenon in a recent article. President Biden leads Donald Trump among Americans who are highly engaged with politics, Nate noted. Yet less engaged voters are so dissatisfied with the country’s condition that they prefer Trump by a wide enough margin to give Trump a small overall lead.

These irregular voters have different concerns on average than politically engaged Americans do. Irregular voters are less likely to focus on hot-button issues that motivate committed Democrats and Republicans, like abortion, immigration and democracy. Irregular voters focus more on pocketbook issues like inflation and health care. They are more likely to say the economy is in bad shape.

I think this pattern helps explain why some of Biden’s core campaign messages have not resonated with swing voters. Biden talks about the country’s soul and pitches himself as a defender of American values, especially democracy. It is an understandable pitch in many ways: Trump is hostile to democratic traditions in a way that no other modern U.S. politician has been.