Section 147(1) in The Representation of the People Act, 1951
(1)When before the expiration of the term of office of a member elected to the Council of States, his seat becomes vacant or is declared vacant or his election to the Council of States is declared void, the Election Commission shall by a notification in the Gazette of India call upon the elected members of the Legislative Assembly or the members of the electoral college concerned , as the case may be, to elect a person for the purpose of filling the vacancy so caused before such date as may be specified in the notification and provisions of this Act and of the rules and orders made thereunder shall apply, as far as may be, in relation to the election of a member to fill such vacancy.