Obama's return to the campaign begins in Green Bay, Wis., where he'll make up an event that was canceled earlier in the week because of the storm. He had a rally planned later in Las Vegas, as well as an event in Boulder, Colo., a heavily Democratic area. Aides said Obama planned to mention the storm victims in his remarks.
Biden had two events scheduled in Iowa.
More than 19 million people have already voted in the presidential election, either by mail or in person. No votes will be counted until Nov. 6, but some key states are releasing the party affiliation of those who have voted.
Democrats have an edge in votes cast in Florida, Iowa, Nevada, North Carolina and Ohio. Republicans have an advantage in Colorado.
Associated Press writer Kasie Hunt in Jacksonville, Fla., contributed to this report.