Would-be voters who are turned away from the polls, told they are not registered or denied provisional ballots can call 1-866-OURVOTE, a toll-free number, for help.

"People will advise them how to deal with the problem," said Barry Kauffman of Common Cause/Pennsylvania, which is helping spread the word about the National Voter Hotline.

Another group, the nonpartisan Election Protection coalition, meanwhile, has a separate hot line manned by trained volunteers who will provide state-specific information on resolving conflicts over voter identification requirements, voting machine malfunctions and voter intimidation.

That effort is led by the American Way Foundation, the NAACP and the Lawyers' Committee for Civil Rights Under Election Law.

To report problems, call the national Election Day hot line at 1-866-OURVOTE. For more information, visit www.EP365.org or www.866OurVote.org.