Closed primaries.

Provides that a voter may vote at a primary election: (1) only if the voter has properly and timely affiliated with a political party; and (2) held by the political party with which the voter affiliates. Allows an individual, not later than December 31 before the date of a primary election, to affiliate with a political party at the time of voter registration or by submitting a party affiliation form. Requires each county voter registration office to mail a party affiliation form to particular voters not later than September 1, 2025.