The Single Transferable Vote
How STV lets voters rank candidates, eliminates the spoiler problem, and is used in Ireland, Australia, and elsewhere.
Ranking Your Preferences
The single transferable vote (STV) is a proportional system that uses multi-member districts and ranked ballots. Voters rank candidates in order of preference: 1, 2, 3, and so on. A quota is calculated (usually the Droop quota: total votes divided by seats-plus-one, then plus one). Any candidate who reaches the quota is elected, and their surplus votes are transferred to the next-ranked candidate on each ballot. If no candidate reaches the quota, the last-place candidate is eliminated and their votes are transferred.
This process continues until all seats are filled. STV is used in Ireland for all elections, in Australia for Senate elections, in Malta, and in a growing number of cities worldwide. Its defining feature is that voters choose between individual candidates rather than parties, making it the most candidate-centered proportional system.
