A permanent system of voter registration by county is established, with a single, official, centralized, interactive computerized statewide voter registration list defined, maintained, and administered at the state level that contains the name and registration information of every legally registered voter in the state, and assigns a unique identifier to each legally registered voter in the state. The interactive computerized statewide voter registration list constitutes the official list of every legally registered voter in the state. The county auditor shall be chief registrar of voters and the chief custodian of the official registration records in each county. The secretary of state is responsible for defining, maintaining, and administering the centralized system.