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 |
Candidate
|
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 | |