CVD homepage
What's new?
Online library
Order materials
Get involved!
About CVD

Introduction to Choice Voting

Choice voting (e.g, "single transferable vote" or "preference voting") is a form of limited voting in which voters maximize their one vote's effectiveness through ranking choices. Choice voting is very likely to provide fair results, can be used in both partisan and non-partisan elections and does not require primaries. It is recommended as the best system for local government elections.

To vote, voters simply rank candidates in order of preference, putting a "1" by their first choice, a "2" by their second choice and so on. Voters can rank as few or as many candidates as they wish, knowing that a lower choice will never count against the chances of a higher choice.

To determine winners, the number of votes necessary for a candidate to earn office is established based on a formula using the numbers of seats and ballots: one more than

1/(# of seats + 1). In a race to elect three seats, the winning threshold would be one vote more than 25% of the vote -- a total that would be mathemetically impossible for four candidates to reach.

After counting first choices, candidates with the winning threshold are elected. To maximize the number of voters who help elect someone, "surplus" ballots beyond the threshold are transferred to remaining candidates according to voters' next-choice preferences: in the most precise method, every ballot is transferred at an equally reduced value. After transferring surplus ballots until no remaining candidate has obtained the winning threshold, the candidate with the fewest votes is eliminated. All of his/her ballots are distributed among remaining candidates according to voters' next-choice preferences. This process continues until all seats are filled. Computer programs have been developed to conduct the count, although the ballot count often is done by hand.

Choice voting has been used for city council elections in Cambridge (MA) since 1941 and is used for Community School Board elections in New York and for national elections in Ireland and Australia. Cambridge's 13% African-American community has helped elect a black candidate in every election since the 1950s; choice voting in other cities -- like New York in the era of Mayor Fiorello La Guardia -- also resulted in fair racial, ethnic and partisan representation.

Example: The chart below illustrates choice voting in a partisan race with 6 candidates running for 3 seats: Jones, Brown and Jackson are Democrats; Charles, Murphy and Stevens are Republicans. With 1000 voters, the threshold of votes needed to win election is 251: (1000/4) + 1.

Note that Democrats Brown and Jones and Republican Charles win, with over 75% of voters helping directly to elect a candidate. Having won 60% of first choice votes, Democrats almost certainly would have won three seats with a winner-take-all, at-large system. (They also would have won three seats with a limited vote system -- and likely with cumulative voting -- because of "split votes" among the Republicans.) Despite greater initial support, Murphy loses to Charles because Murphy is a polarizing candidate who gains few transfer votes. Finally, 45 of 345 voters who help elect Brown in the fourth count chose not to rank Charles and Murphy, which "exhausts" their ballots.

1st Count 2nd Count 3rd Count 4th Count 5th Count
Jones wins
Jones' surplus transferred Smith's votes transferred Jackson's votes transferred Brown's votes transferred
Brown (D) 175 +10 = 185 + 10 = 195 +150 = 345 - 94 = 251
Jones (D) 270 -19 = 251 - - -
Jackson (D) 155 + 6 = 161 + 6 = 167 - 167 = 0 -
Charles (R) 130 + 2 = 132 + 75 = 207 + 14 = 221 + 44 = 265
Murphy (R) 150 + 0 = 150 + 30 = 180 + 3 = 183 + 5 = 188
Smith (R) 120 + 1 = 121 -121 = 0 - -
Exhausted - - - - + 45 = 45

top of page

Copyright 2002     The Center for Voting and Democracy
6930 Carroll Ave. Suite 610, Takoma Park, MD 20912
(301) 270-4616        [email protected]