A city primary election shall be held on the Tuesday following the first Monday in August of each odd-numbered year unless otherwise provided in this charter. No primary shall be conducted unless there are more than twice the number of candidates for the vacancies to be filled. The number of candidates receiving the highest number of votes equal to twice the number of vacancies to be filled at the election shall be certified by the City Clerk and listed on the general election ballot. No candidate shall be deemed elected at such primary.