For mail-in voting, voters casting a mail-in ballot will have to add two new pieces of information to their affidavit: their date of birth and a voter ID number. The voter ID number can be the number on a voter’s driver's license or government issued ID number, or the last four digits of their social security number. Currently, the voting affidavit only requires the signature of the voter. This signature is verified by comparing it to the voter’s signature on record with voter registration documents.