Different uses for voting need different types of voting.
Single Transferable Vote
How can we give more voters the power to nominate candidates?
Here is an analogy: Each candidate puts out a box. A voter puts his ballot in his favorite candidate's box. The ballots are counted. If the box gets enough ballots, it wins. If not, the voter moves his ballot to another candidate's box. Or, he waits, hoping others will move their ballots to his favorite box. To break that deadlock, we have a rule: If a round of counting ballots finds no winner, the box with the fewest votes is eliminated. Its ballots go to each voter's backup (2nd) choice – probably someone with similar views and more popularity.
These transfers make voters condense into large groups supporting strong candidates. Ballots are counted again to see if any candidate gets a winning share of the current top ranks.
When half of all ballots are in 1 candidate’s box, she wins a single-seat STV election. In the UK that is called the Alternative Vote, and Australians call it Preferential Voting. In the USA, it's called Instant Runoff Voting, which is one type of Ranked-Choice Voting.
A box needs less than half the ballots to win a seat on a council. To win 1 of 5 seats requires the top rank on only one-fifth of the ballots or 20%. An interest group with 20% of the voters will win 1 seat after moving their ballots, no matter how many extra candidates they start with. A group with 60% of the voters will win 3 seats and only 3. That is their fair share and their Proportional Representation (PR). If a candidate gets more than enough votes, a share of the extra votes goes to each supporter's next choice.
In practice, each voter ranks the candidates as 1st choice, 2nd choice, 3rd etc. Then officials move ballots between boxes or a computer tallies them.
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Most people want PR when they taste its benefits. So the voting workshop teaches transferable votes by voting for treats!
Voting is easy. Sorting ballots for a big STV election was hard, but free software now makes an STV tally easy for any group. Programs to tally STV are available on the Tool page.
The next page graphically shows how an STV tally works to protect the majority's right to a majority of seats; the page after that shows how STV works at the same time to protect the rights of a large political minority.
(1) STV stands for Single Transferable Vote. STV means Single Transferable Vote. Many people in the USA prefer the term “Choice Voting” which is one kind of “Ranked-Choice Voting”. Australians call it the “Hare–Clark Proportional” method, Voters in some countries call it “Preference Voting” or “Preferential Voting”.