California Code, Elections Code - ELEC § 8454

(a) Circulators obtaining signatures to the nomination paper of any candidate may, at any time not more than 148 nor less than 88 days prior to the election, obtain signatures to the nomination paper of the candidate.

(b) Circulators obtaining signatures to the nomination paper of any candidate for presidential elector may, at any time not more than 193 nor less than 88 days prior to the election, obtain signatures to the nomination paper of the candidate.