Vote counting explainer

Counting Method

• RCV123 uses the common ranked choice voting method of counting the first place votes, then eliminating the candidate with the fewest votes and reallocating those votes to the candidates ranked second on those ballots. This process repeats until one candidate exceeds 50%. The method is slightly different for single-winner and multi-winner contests.
• RCV123 uses the standard WIGM RCV counting method, with one exception having to do with ties. See our Tiebreaking explainer for details.

Single Winner

• Voters cast one ballot, but when there are three or more candidates for one office, voters have the option to rank candidates in the order they prefer them: 1st, 2nd, 3rd, etc.
• Ballots are initially counted for each voter’s top choice. If one candidate receives a majority of the first-choice votes, that candidate wins and the counting is no different than a conventional election.
• If no candidate receives a majority of the first-choice votes, the votes get counted in a series of rounds. The candidate with the fewest first- choice votes is eliminated and the votes they received count instantly towards their supporter’s next choice. The process repeats with one candidate being eliminated in each round, and those votes get transferred to their voter’s next choices, until a candidate receives a majority of the vote and wins.

Multi-Winner Counting

• Multi-winner has a formula to set the vote threshold each candidate needs to win. It’s the number of votes at the beginning of the contest divided by the number of seats up for election, plus one. If that answer is a whole number, add 1 to it. If the answer is a decimal, round up to the nearest whole number.
• If four seats are available on a council, and there are 101 voters, then the threshold to win is 101 divided by (4+1). 101/5 = 20.2. That number is rounded up to the nearest whole number. So, in this example, any candidate reaching 21 votes is declared a winner.
• The policy behind the math is simple. 4 seats x the threshold of 21 = 84. 101-84 = 17. Even if all the remaining votes were cast for a 5th candidate, that candidate would only have 17 votes, and the other four would each have 21.
• If the threshold were 20 instead of 21, then five candidates could meet the winning threshold, but there are only four seats to fill. 5 x 20 = 100. (There are 101 votes in this election.)
• This is a complex aspect to multi-winner RCV. Most RCV education does not venture into this level of detail. Members of the public rarely express curiosity about it. The idea that votes above the threshold are transferred makes conceptual sense, and questions rarely are asked about the mechanics.
• The issue may come up when a user of the RCV123 app sees a multi-winner election result that has a vote total that ends with a decimal.
• Returning to the example above, if a candidate reaches 23 votes and the threshold is 21, then they have 23-21 = 2 excess votes.
• For each ballot that contributed to that winner’s 23 votes, 21/23, or .913 of each vote is set aside, and 2/23, or 0.0869 of each vote continues on to the subsequent choices on those ballots.
• In plainer terms, the votes that help a candidate win are set aside, or used up. But the portion of votes received above the threshold are still available to contribute to other winners.
• If all of a winner’s votes were able to re-circulate to other winners, then a single coalition could, over rounds of counting, elect all the winners of a multi-winner election.
• Multi-winner RCV is designed to help elect a somewhat proportional set of candidates that reflects the entire population of voters. Having the votes for a winner get set aside allows the voters whose candidates have not reached the threshold to come into play.