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The National Mail Voter Registration Form can be used to register U.S. citizens to vote, to update registration information due to a change of name, make a change of address or to register with a political party. You must follow the state-specific instructions listed for your state. They begin on page 3 of the form and are listed alphabetically by state. After filling out this form, you must sign your name where indicated and send it to your state or local election office for processing.