§ 145.001. METHOD FOR WITHDRAWAL AS CANDIDATE.
(a) To withdraw from an election, a candidate whose name is to appear on the ballot must request that the candidate's name be omitted from the ballot.
(b) To be effective, a withdrawal request must:
(1) be in writing and be signed and acknowledged by the candidate; and
(2) be timely filed with the appropriate authority as provided by this code.
(c) A withdrawal request filed by mail is considered to be filed at the time of its receipt by the appropriate authority.
(d) The time of a withdrawal is the time that an effective withdrawal request is filed.
(e) This section does not apply to a candidate for president or vice-president of the United States
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How could DeLay have withdrawn if he didn't do it by writing? It doesn't appear a judge may administratively withdraw a candidate.