The key to these undecided voters' late-breaking decisions - and the election - won't be the campaign promises the candidates have made. It will be to what extent they trust each candidate to carry out his promises.
These voters won't be swayed by complex policy positions. Ultimately, they will vote for the man they trust more - the one they feel has made the better case that he can govern with integrity. Among independents, this is often seen as the best hope for breaking the gridlock in Washington.
At this point, the trust question seems to favor Romney slightly. Asked whom they trust on the economy, voters narrowly prefer him in the latest results from the Washington Post-ABC News tracking poll. This is important because it's partly a question of "trust." The poll also shows independents preferring Romney.
President Dwight D. Eisenhower once said, "I despise people who go to the gutter on either the right or the left and hurl rocks at those in the center." The undecided voters are those in the center. They will be seeking the kind of centrist leader Eisenhower was - someone who can end this period of incredible political polarization.
Distrust between the parties has led to an angry and confused electorate. Whether or not they recall Eisenhower, the voters who will decide this race will intuitively prefer the candidate they trust to end the gridlock.
Jennifer Donahue is a Cardin fellow of public policy and expert in residence at Gettysburg College's Eisenhower Institute, and a political commentator who has appeared widely on television and in print.