Comment: It's explained here

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It's explained here

"A provisional ballot is used to record a vote when there are questions in regards to 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. Many voters do not realize that the provisional ballot is not counted until 7–10 days after election so their vote does not affect the calling of the states to different candidates.

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."