Texas Election Code - ELEC § 162.001. Affiliation with Party Required

(1) to serve as a delegate to or otherwise participate in a convention held by the party under this code;

(2) to be elected as a member of or be appointed to fill a vacancy on a state executive committee;

(3) to be appointed to fill a vacancy on a county executive committee;  or

(4) for any other purpose within the party as adopted by state party rules.

(1) general primary election day, for a party holding a primary election;  or

(2) the date of the precinct conventions held under this title, for a party nominating by convention.