How RCV Works
Ranked Choice Voting is the familiar runoff process done in a single election. Under the system, all ballots are tallied according to first-place choices. In a single-winner election, if one candidate wins a majority (50% + 1) among all first-place votes, that candidate is the winner.
If not, the candidate with the fewest first-place votes is eliminated and the ballots for this candidate are redistributed among the remaining candidates according to the second choices on those ballots. The process continues until one candidate has picked up a majority of votes.
Ranked Choice Voting works equally well when there are multiple seats to fill. The threshold for winning is adjusted depending on the number of seats to fill and a similar process of eliminating and electing candidates and redistributing votes occurs until all the seats are filled.
Ranked Choice Voting Ballot
Complete the ballot by ranking candidates in order of preference.
Counting single seat office elections
Example, Office of Mayor or City Council District
Determine the threshold needed to win.
In a single-seat election, the threshold to win is 50% + 1 vote:
How the votes are counted
The first choice votes are sorted and counted. If the votes for any candidate equal or exceed the threshold, that candidate is the winner.
If no candidate receives the required number of votes to win, the candidates with the fewest votes are eliminated in a series of rounds.
The votes of the eliminated candidates are reallocated to the remaining candidates in accordance with the second and third choices marked on those ballots by the voters.
The rounds continue until one candidate has more than half of the votes or, when only two candidates remain, has more votes than the other candidate.
Example
The threshold needed to win is 5,001 votes (10,000/2 + 1 vote)
| Round 1 | The first choice votes are counted. No candidate has received a majority of the votes cast |
| Round 2 | Because no candidate reached the threshold, the candidate with the fewest votes – Candidate E – is eliminated and the votes cast for this candidate are reallocated to the voters’ second choice candidates.
The votes for Candidate E are redistributed and go to Candidate A and B in accordance with the voters’ second choices. No candidate has a majority of the votes. |
| Round 3 | Candidate D now has the fewest votes and so is eliminated. Candidate D’s ballots are redistributed, but 200 of the ballots did not have a next choice marked on the ballot and are set aside as ‘exhausted’. The other 1,200 votes get redistributed to the continuing candidates in accordance with the voters’ next preferences.
Candidate A now has a majority of the votes and so is the winner. |
Counting multiple seat office elections
Example, two seats for Board of Estimate & Taxation and three seats for Park Board at large
Determine the threshold needed to win.
In a two-seat election, the threshold to win is 33% + 1:
How the votes are counted
Multiple seat counts are a little different but still quite easy.
The first choice votes are sorted and counted. Any candidate whose vote equals or exceeds the threshold is elected.
If any candidate has more votes than the threshold, that ‘surplus' above the threshold is transferred, unless the surplus is too small to affect the elimination of the bottom candidate.
All the ballots are transferred to remaining candidates in accordance with the second choices on the elected candidate's ballots. The surplus votes are transferred in proportion to the number of ballots each remaining candidates receives.
If after the surpluses have been transferred some seats remain to be filled, the candidate with the fewest votes is eliminated and that candidate's votes are transferred in accordance with the next preference marked on those ballots.
The transfers of votes continue, round by round, until all seats are filled.
Examples of multi-seat elections are the Minneapolis Board of Estimate (2 seats) and Taxation and Park Board (3 seats).
Example
The threshold needed to win is 3334 votes (10,000/3 + 1 vote)
| Round 1 | The first choice votes are counted. Candidate A has reached the threshold and so is declared the first winner. There is still one more seat to be filled. |
| Round 2 | Candidate A has more votes than the threshold – a surplus of 666 votes. The ballots that have Candidate A as their first choice are redistributed to the second choice candidate on each of those ballots. All 4,000 ballots are transferred, but at a fraction of a vote (666/4000 or .1665) so that only the 666 surplus votes are transferred in total.
Candidate C is the second choice on 3,000 of the 4,000 ballots and so 499.5 votes are transferred to Candidate C. Candidate D is the second choice on 1,000 of the 4,000 ballots and so 166.5 votes are transferred to Candidate D. |
| Round 3 | No other candidate has yet reached the threshold and so another round of transfers occurs. Candidate D is the candidate with the fewest votes and is eliminated.
The votes for Candidate D are redistributed to the two remaining candidates based on the next preferences indicated on the voters’ ballots – 116.5 go to Candidate B and 950 to Candidate C. A total of 100 voters did not mark a next preference and those ballots are ‘exhausted’. Candidate C has reached the threshold and is declared the second winner. |