California Code, Public Utilities Code - PUC § 15966

(a) Not less than 30 days prior to the election, any five or more electors in the district may file with the board of directors a petition requesting that the names of certain persons specified in the petition be placed upon the ballot as candidates for the office of director at large.

(b) Not less than 30 days prior to the election, any five or more electors of a territorial unit may file with the board of directors a petition requesting that the name of a designated person specified in the petition be placed upon the ballot as candidate for the office of director from the territorial unit.