The judges of each district council shall elect a superior court judge or a senior judge of the superior court to serve for a two-year term as an "administrative judge" within the district. The district administrative judge shall serve until his successor is elected and qualified; provided, however, that the district administrative judge may be removed at any time by a two-thirds' vote of all judges comprising the district council. The duties of the administrative judge shall be additional duties which shall not be construed to diminish his other responsibilities.