Me. Const. art. IV, pt. 1, § 4

Qualifications; residency requirement. No person shall be a member of the House of Representatives, unless the person shall, at the commencement of the period for which the person is elected, have been 5 years a citizen of the United States, have arrived at the age of 21 years, have been a resident in this State one year; and for the 3 months next preceding the time of this person's election shall have been, and, during the period for which elected, shall continue to be a resident in the district which that person represents. No person may be a candidate for election as a member of the House of Representatives unless, at the time of the nomination for placement on a primary, general or special election ballot, that person is a resident in the district which the candidate seeks to represent.