At the biennial state election there shall be chosen by the voters of the commonwealth, as prescribed by the constitution, a governor, lieutenant governor, state secretary, state treasurer, state auditor and attorney general; by the voters in each councillor district, one councillor; by the voters in each senatorial district, one senator; and by the voters in each representative district, such number of representatives as the district is entitled to elect.
Mass. Gen. Laws ch. 54, § 150