Texas Election Code - ELEC § 162.008. Affiliation Procedure:  Taking Oath Generally

(a) A person may affiliate with a political party at any time by taking an oath of affiliation.

(b) On request of a person desiring to affiliate with a political party, a member of the county executive committee for the county in which the person resides or other person authorized by party rule shall administer the following oath:  “I swear that I have not voted in a primary election or participated in a convention of another party during this voting year.  I hereby affiliate myself with the __________ Party.”

(c) After administering the oath, the committee member or authorized person may stamp the party's name in the party affiliation space unless the party name has already been stamped in the space.  If the person does not present a registration certificate, the committee member or authorized person on the person's request shall issue the person an affiliation certificate.