Michael Waldman, president of the Brennan Center for Justice at New York University, said even in states where the restrictive laws have been blocked or delayed, many people still think they are in effect.
‘‘The laws were struck down but the confusion remains,’’ Waldman said.
Many of these issues could resurface in the courts after Tuesday, particularly if the race between Obama and his Republican challenger, Mitt Romney, is too close to call or heads for a recount in states such as Ohio or Florida.
The Justice Department will have at least 780 observers at key polling places in 23 states to ensure compliance with the 1965 Voting Rights Act and look into any allegations of voter fraud.
Provisional ballots were the latest legal skirmish in the critical battleground state of Ohio, where Secretary of State Jon Husted’s decision on how they can be cast was challenged in federal court. Advocates and lawyers for labor unions contend Husted’s order would lead to some provisional ballots being rejected improperly because the burden of recording the form of ID used on a provisional ballot is being placed on voters, not poll workers as in the past.
A provisional vote allows a person to have his or her say, but the ballot is subject to review and verification of eligibility. A court hearing was set for Wednesday on issue. Provisional ballots cannot be counted in Ohio before Nov. 17.
Contributing to this report were Associated Press writers A.J. Connelly in New York, Andrew Welsh-Huggins in Columbus, Ohio, and Patrick Walters in Philadelphia.
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