When the provisions of this charter require the council to submit the proposal to the electors, it shall be submitted at the next election held in the city for any other purpose, or in the discretion of the council, at a special election. In any event, it shall be submitted at an election where there is sufficient time for the processing of the notice of registration and of election and providing for absentee ballots. The results shall be determined by a majority vote of the electors voting thereon, except in cases where otherwise required by law.