Article IV. — Part Second.
Section 1. Number of Senators. The Senate shall consist of an odd number of Senators, not less than 31 nor more than 35, elected at the same time and for the same term as Representatives by the qualified electors of the districts into which the State shall be from time to time divided.
Section 2. Submission of reapportionment plan to Secretary of Senate; Legislature’s action on commission’s plan; division of State into Senatorial Districts; division by Supreme Judicial Court. The Legislature which shall convene in the year 1983 and every tenth year thereafter shall cause the State to be divided into districts for the choice of a Senator from each district, using the same method as provided in Article IV, Part First, Section 2 for apportionment of Representative Districts.
The apportionment plan of the commission established under Article IV, Part Third, Section 1-A shall be submitted to the Secretary of the Senate no later than 120 calendar days after the convening of the Legislature in which apportionment is required. In the preparation of legislation implementing the plan, the commission, following a unanimous decision by commission members, may adjust errors and inconsistencies in accordance with the standards set forth in this Constitution, so long as substantive changes are not made. The Legislature shall enact the submitted plan of the commission or a plan of its own by a vote of 2/3 of the Members of each House, within 30 calendar days after the plan of the commission is submitted. Such action shall be subject to the Governor’s approval as provided in Article IV, Part Third, Section 2.
In the event that the Legislature shall fail to make an apportionment within 130 days after convening, the Supreme Judicial Court shall, within 60 days following the period in which the Legislature is required to act but fails to do so, make the apportionment. In making such apportionment, the Supreme Judicial Court shall take into consideration plans and briefs filed by the public with the court during the first 30 days of the period in which the court is required to apportion.
The Supreme Judicial Court shall have original jurisdiction to hear any challenge to an apportionment law enacted by the Legislature, as registered by any citizen or group thereof. If any challenge is sustained, the Supreme Judicial Court shall make the apportionment.
Section 3. Election of Senators; lists of votes delivered forthwith. The meetings within this State for the election of Senators shall be notified, held and regulated and the votes received, sorted, counted, declared and recorded, in the same manner as those for Representatives. Fair copies of the lists of votes shall be attested by the clerks of the cities and towns or other duly authorized officials and sealed up in open meetings and such officials shall cause said lists to be delivered into the office of the Secretary of State forthwith.
Section 4. Lists of votes examined by Governor; summons to persons who appear to be elected. The Governor shall, as soon as may be, examine the copies of such lists, and at least 7 days before the said first Wednesday of December, issue a summons to such persons, as shall appear to be elected by a plurality of the votes in each senatorial district, to attend that day and take their seats.
Section 5. Determination of Senators elected; procedure for filling vacancies. The Senate shall, on said first Wednesday of December, biennially determine who is elected by a plurality of votes to be Senator in each district. All vacancies in the Senate arising from death, resignation, removal from the State or like causes, and also vacancies, if any, which may occur because of the failure of any district to elect by a plurality of votes the Senator to which said district shall be entitled shall be filled by an immediate election in the unrepresented district. The Governor shall issue a proclamation therefor and therein fix the time of such election.
Section 6. Qualifications. The Senators shall be 25 years of age at the commencement of the term, for which they are elected, and in all other respects their qualifications shall be the same as those of the Representatives.
Section 7. To try impeachments; limitation of judgment of impeachment; party liable to be tried and punished in court. The Senate shall have the sole power to try all impeachments, and when sitting for that purpose shall be on oath or affirmation, and no person shall be convicted without the concurrence of 2/3 of the members present. Their judgment, however, shall not extend farther than to removal from office, and disqualification to hold or enjoy any office of honor, trust or profit under this State. But the party, whether convicted or acquitted, shall nevertheless be liable to indictment, trial, judgment and punishment according to law.
Section 8. To choose own officers. The Senate shall choose their President, Secretary and other officers.
Source: http://maine.gov/legis/const/ (accessed October 26, 2011)