Me. Rev. Stat. tit. 24-A, § 4361

A certified copy of any order to show cause issued under section 4360, and a copy of the petition upon which the same is made, must be served upon the insurer by delivering the same to its president, vice-president, secretary, treasurer, director or to its managing agent or attorney in fact, if a reciprocal insurer; or if no such officer or functionary can readily be found in this State, then such process may be served upon the insurer by service thereof upon the superintendent pursuant to section 421.