A vacancy exists in the membership under any of the following circumstances:

1. (a) When there is no “holdover delegate” nor “nominee delegate” of the party.
2. (b) When any nominee is disqualified for membership under the provisions of Section 7555 or for any other reason stated in this division.
3. (c) When no nomination for an elective office has been made.
4. (d) When a delegate dies prior to the convention.