Maine Constitution Art. V, Pt. 1, § 14. Vacancy, how supplied

Section 14. Whenever the office of Governor shall become vacant because of the death, resignation or removal of a Governor in office, or any other cause, the President of the Senate shall assume the office of Governor until another Governor shall be duly qualified. When the vacancy occurs more than 90 days preceding the date of the primary election for nominating candidates to be voted for at the biennial election next succeeding, the President of the Senate shall assume the office of Governor until the first Wednesday after the first Tuesday of January following the biennial election. At the biennial election, a Governor shall be elected to fill the unexpired term created by the vacancy. When the vacancy occurs less than 90 days preceding the date of a primary election the President of the Senate shall fill the unexpired term.

Whenever the offices of Governor and President of the Senate are vacant at the same time, the Speaker of the House of Representatives shall assume the office of Governor for the same term and under the same conditions as the President of the Senate.

Whenever the offices of Governor, President of the Senate and Speaker of the House of Representatives are vacant at the same time, the person acting as Secretary of State for the time being shall exercise the office of Governor and shall forthwith by proclamation convene the Senate and the House of Representatives which shall fill respectively the vacancies in the offices of the President of the Senate and the Speaker of the House, and by joint ballot of the Senators and Representatives in convention choose a person who shall assume the office of Governor for the same term and under the same conditions as the President of the Senate.

Mental or physical disability of the Governor continuously for more than 6 months.

Whenever for 6 months a Governor in office shall have been continuously unable to discharge the powers and duties of that office because of mental or physical disability such office shall be deemed vacant. Such vacancy shall be declared by the Supreme Judicial Court upon presentment to it of a joint resolution declaring the ground of the vacancy, adopted by a vote of 2/3 of the Senators and Representatives in convention, and upon notice, hearing before the court and a decision by a majority of the court that ground exists for declaring the office to be vacant.