Me. Rev. Stat. tit. 21-A, § 442

On or before October 1st of the year prior to a presidential election year, the Secretary of State shall prepare and make available petitions for circulation by a person desiring to be a candidate in the state presidential primary election of any party. Petitions must be delivered to the registrar, or clerk at the request or upon the absence of the registrar, for certification by 5 p.m. on November 20th of the year prior to a presidential election year. Petitions must be completed and filed with the Secretary of State no later than 5 p.m. on December 1st of the year prior to a presidential election year in the manner provided in sections 335 and 336.