Substitute (elections)
A substitute is a political candidate who is not directly elected, but who succeeds a politician holding an elected office after that person ceases to hold the office due to, for example, resignation or death. This system can be used to fill casual vacancies instead of holding by-elections or special elections to fill the vacant office. Substitutes are nominated, not at the time the vacancy arises but, rather, before the election for the information of voters. In voting systems which use electoral lists, the candidates on a given list who are not among those initially elected may become the substitutes for those who are. In other systems, individual candidates may have substitutes.