Countback

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A joint Politics and Economics series
Social choice and electoral systems
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The countback method is a way of filling casual vacancies in proportional voting systems. Casual vacancies are filled by re-examining the ballots from the previous election. The candidate who held the seat is eliminated, and the election is then re-run with this candidate removed. Unlike other methods of filling vacancies, this procedure maintains proportional representation, and eliminates the need for expensive and low-turnout special elections.