BEDFORD, N.H. — After all the months of campaigning, advertising, and debating, the presidential campaign is coming down to scenes like this: Dianne Bzik and Betty HoSang, suburban moms who volunteered for President Obama, meander through neighborhoods and knock on doors, asking if residents need an absentee ballot or a ride to the polls or an answer to a last-minute question.

Hundreds of miles away in Ohio a nearly identical scene played out as Deb Voss and Karen Schreckenhofer canvassed a Cincinnati suburb for Mitt Romney. They too were carrying their cause door to door on an autumn afternoon.