provisional ballot

A provisional ballot is used to record a vote when there are questions about a given voter’s eligibility. A provisional ballot would be cast when:

The voter refuses to show a photo ID (in regions that require one)
The voter’s name does not appear on the electoral roll for the given precinct.
The voter’s registration contains inaccurate or out-dated information such as the wrong address or a misspelled name.
The voter’s ballot has already been recorded
Whether a provisional ballot is counted is contingent upon the verification of that voter’s eligibility.

A guarantee that a voter could cast a provisional ballot if he or she believes that they are entitled to vote was one of the guarantees of the Help America Vote Act of 2002.