Cumulative voting (sometimes called the single divisible vote) is an election system where a voter casts multiple votes but can lump votes on a specific candidate or can split their votes across multiple candidates. The candidates elected are those receiving the largest number of votes cast in the election, up to the number of representatives to be elected.
Cumulative voting can simplify strategic voting, by allowing larger groups of voters to elect multiple representatives by splitting their vote between multiple candidates. This removes the complexity associated with randomized or coordinated strategies.
It may be thought of as a variant of block voting. Under both cumulative voting and block voting, a voter casts multiple votes but in the case of cumulative voting, can lump them all on one candidate (the equivalent of engaging in plumping). When voters do this, the result is similar to SNTV. When supporters of a minority candidate do this, they may be of sufficient strength to elect that minority representative, not a likely occurrence under either first past the post voting or block voting. Thus, cumulative voting generally produces similar results to SNTV (especially if voters are informed and rational, in which case they will tend to engage in plumping. Plumping though reduces cumulative voting's effectiveness at reducing need for strategic voting by allowing the voter to cast a split vote.).
Cumulative voting can also be thought of as a form of cardinal voting: a variant on score voting where the total scores for each candidate must add up to a fixed value (e.g. 100%). If instead the sum of squares must add up to a fixed value, the method becomes quadratic voting.[1][2]
Cumulative voting was used to elect the Illinois House of Representatives[5] from 1870 until its repeal in 1980[6][7][8] and used in England and Scotland in the late 19th century to elect some school boards. As of March 2012, more than fifty communities in the United States use cumulative voting, all resulting from cases brought under the National Voting Rights Act of 1965. Among them are Peoria, Illinois for half of its city council, Chilton County, Alabama for its county council and school board, and Amarillo, Texas, for its school board and College Board of Regents.[9] Courts sometimes mandate its use as a remedy in lawsuits brought under the Voting Rights Act in the United States; an example of this occurred in 2009 in Port Chester, New York[10][11] which had its first cumulative voting elections for its board of trustees in 2010.[12]
Voting options
Cumulative voting was also used to elect city boards in Toronto, Canada starting in 1904. The Proportional Representation Review (September 1903) described it like this:
Cumulative voting as applied to the Board of Control, means that each elector will have four votes but that he need not give each of them to a different candidate. He may do so if he wishes; but he has also the power to give all his four votes to one candidate. This makes "plumping" four times as powerful as it was by the old "block" vote system, when if you "plumped" for one candidate, you threw away three out of your four votes. Now you have the benefit of your full voting power, whether you plump or not. And plumping is the correct thing; in fact proportional representation is simply effective representation with the addition in the best systems of a provision for transfer of votes, so as to prevent wasting too many on one candidate...
Besides permitting an elector to give all four votes to one candidate, the cumulative plan enables him to give two of his votes to one candidate and two to another, or he may give three votes to one candidate and his fourth to another candidate. In fact he may distribute or cumulate his four votes as he pleases....
If one-fourth of the voters give all their votes to one candidate, they can elect him, no matter what the other three-fourths choose to do[...] thus Cumulative Voting if used carefully allows for minority representation.[13][unreliable source?]
A form of cumulative voting has been used by group facilitators as a method to collectively prioritize options, for example ideas generated from a brainstorming session within a workshop. This approach is described as "multi-voting" and was likely derived from the nominal group technique and is one of many tools suggested within the Six Sigma business management strategy.[14]
Voting
In equal and even voting, points are equally divided between all supported candidates.
Cumulative voting is used in elections where more than one seat is filled. It permits voters to cast multiple votes, as many as the number of seats to be filled, allows each voter to put more than one vote on a preferred candidate. When voters in the minority concentrate their votes in this way for just one candidate, it increases their chances of obtaining representation in a legislative body. This is different from bloc voting, where a voter may not vote more than once for any candidate and the largest single block, even if less than 50 percent, can control all the representation elected in the district.
Fractional vote ballotSticker dot voting
Permissible splits
Cumulative voting systems differ both in the ways voters mark their selections and in the degree to which voters are permitted to split their votes.
Equal-and-even
Possibly the simplest ballot is called satisfaction approval voting or the equal-and-even method. On this ballot, a voter simply marks all candidates they approve of, as in approval voting, and their vote is automatically distributed evenly among those preferred candidates. Voters are unable to specify a differing level of support for a more preferred candidate, giving them less flexibility but simplifying ballot completion.
Dot voting
A more common and slightly more complex cumulative voting system is called dot voting[15] or multi-voting.[16] Under this method, voters are given an explicit number of points, which they can distribute among one or more candidates on the ballot. Typically, this is done by having a voter make one mark for each point they wish to assign to the desired candidate. In dot-voting participants vote on their chosen options using a limited number of stickers or marks with pens — dot stickers being the most common. This sticker voting approach is a form of cumulative voting. Dot-voting is now widely used for making quick collaborative decisions by teams adopting agile and lean methodologies. For example, it is one of the methods endorsed by the 18F digital services agency of the United States' General Services Administration, and is part of the Design Sprint methodology.
Generally, the number of points given to each voter is equal to the number of winning candidates (seats to be filled), which is typically a holdover after a transition from block plurality voting.
Fractional voting
A similar method is to have the voter write in a desired number of points next to each candidate. Then, the scores on the ballot are divided by the total number of points the voter has assigned, to make sure the allocation adds up to 100%. The need to normalize votes complicates counting by hand, but simplifies the process of voting and gives each voter maximum flexibility.
Properties
Advocates of cumulative voting often argue that political and racial minorities deserve better representation. By concentrating their votes on a small number of candidates of their choice, voters in the minority can win some representation—for example, a like-minded grouping of voters that is 20% of a city would be well-positioned to elect one out of five seats. All forms of cumulative voting achieve this objective (although if two or more candidates of that minority run in the same election, vote splitting may deny the group its possible representation).
In a corporate setting, challengers of cumulative voting argue that the board of directors gets divided and this hurts the company's long term profit. Using a staggered board of directors can diminish the ability of minority factions to obtain representation by reducing the number of seats up for election at any given time.[17]
Robert's Rules of Order Newly Revised states that groups may adopt cumulative voting in its by-laws, and notes that "A minority group, by coordinating its effort in voting for only one candidate who is a member of the group, may be able to secure the election of that candidate as a minority member of the board."[18]
Use
The Norfolk Island Legislative Assembly on Norfolk Island was elected using a form of cumulative voting where voters cannot give all their votes to one candidate. It is also used heavily in corporate governance, where it is mandated by seven U.S. states, and it was used to elect the Illinois House of Representatives from 1870 until 1980.[5][6] It was used in England between 1870 and 1902, under the Elementary Education Act 1870, to elect school boards. Starting in the late 1980s, it has been adopted in a growing number of jurisdictions in the United States. Generally, this has been in an attempt to resolve lawsuits brought against bloc voting methods.[19]
With strategic voting, one can calculate how many shares are needed to elect a certain number of candidates, and to determine how many candidates a person holding a certain number of shares can elect.
Some Bugzilla installations allow the use of cumulative voting to decide which software bugs most urgently need correcting.[20]
Tactical voting
Voters in a cumulative election can employ different strategies for allocating their vote.
Plumping
Plump voting occurs when a voter assigns all their points to the same candidate.[21] The issue of "Plumper Votes" was heavily discussed in the early 18th century, when Sir Richard Child was returned for Essex in 1710 with 90% of his votes having been "Plumpers".[22]
Quota
The formula to determine the number of votes needed to elect one seat is called the Droop quota and has value:
Plurality voting refers to electoral systems in which the candidates in an electoral district who poll more than any other are elected.
Proportional representation (PR) refers to any type of electoral system under which subgroups of an electorate are reflected proportionately in the elected body. The concept applies mainly to political divisions among voters. The essence of such systems is that all votes cast – or almost all votes cast – contribute to the result and are effectively used to help elect someone. Under other election systems, a bare plurality or a scant majority are all that are used to elect candidates. PR systems provide balanced representation to different factions, reflecting how votes are cast.
Party-list proportional representation (list-PR) is a system of proportional representation based on preregistered political parties, with each party being allocated a certain number of seats roughly proportional to their share of the vote.
The single transferable vote (STV) or proportional-ranked choice voting (P-RCV) is a multi-winner electoral system in which each voter casts a single vote in the form of a ranked ballot. Voters have the option to rank candidates, and their vote may be transferred according to alternative preferences if their preferred candidate is eliminated or elected with surplus votes, so that their vote is used to elect someone they prefer over others in the running. STV aims to approach proportional representation based on votes cast in the district where it is used, so that each vote is worth about the same as another.
Single non-transferable vote or SNTV is an electoral system used to elect multiple winners. It is a semi-proportional variant of first-past-the-post voting, applied to multi-member districts where each voter casts just one vote. It can also be seen as a variant of limited voting where each elector votes only once.
Block or bloc voting refers to a class of electoral systems where multiple candidates are elected simultaneously. They do not guarantee minority representation and allow a group of voters to ensure that only their preferred candidates are elected. In these systems, a voter can select as many candidates as there are open seats. That is, the voter has as many votes to cast as the number of seats to fill. The block voting systems are among various election systems available for use in multi-member districts where the voting system allows for the selection of multiple winners at once.
An electoraldistrict, sometimes called a constituency, riding, or ward, is a geographical portion of a political unit, such as a country, state or province, city, or administrative region, created to provide the voters therein with representation in a legislature or other polity. That legislative body, the state's constitution, or a body established for that purpose determines each district's boundaries and whether each will be represented by a single member or multiple members. Generally, only voters (constituents) who reside within the district are permitted to vote in an election held there. The district representative or representatives may be elected by single-winner first-past-the-post system, a multi-winner proportional representative system, or another voting method.
The Illinois House of Representatives is the lower house of the Illinois General Assembly. The body was created by the first Illinois Constitution adopted in 1818. The House under the current constitution as amended in 1980 consists of 118 representatives elected from individual legislative districts for two-year terms with no limits; redistricted every 10 years, based on the 2010 U.S. census each representative represents approximately 108,734 people.
Limited voting is a voting system in which electors have fewer votes than there are positions available. The positions are awarded to the candidates who receive the most votes. In the special case in which the voter may vote for only one candidate and there are two or more posts, this system is called the single non-transferable vote or sometimes the strictly limited vote.
FairVote is a 501(c)(3) organization and lobbying group in the United States. It was founded in 1992 as Citizens for Proportional Representation to support the implementation of proportional representation in American elections. Its focus changed over time to emphasize instant-runoff voting (IRV), a national popular vote, and universal voter registration. It changed its name to the Center for Voting and Democracy in 1993 and to FairVote in 2004.
Bullet, single-shot, or plump voting is when a voter supports only a single candidate, typically to show strong support for a single favorite.
The Cutback Amendment is an amendment to the Illinois Constitution that abolished multi-member districts in the Illinois House of Representatives and the process of cumulative voting. Before the amendment, the Illinois General Assembly was divided into 59 legislative districts, each of which elected one senator and three representatives. In state house elections, voters could vote three times for one candidate or spread their votes between two or three candidates. When the Cutback Amendment was approved in 1980, the total number of House representatives was reduced from 177 to 118 and members were elected from single-member districts formed by dividing the 59 Senate districts in half. The movement to pass the bill was largely led by Democrats Pat Quinn and Harry Yourell.
At large is a description for members of a governing body who are elected or appointed to represent a whole membership or population, rather than a subset. In multi-hierarchical bodies, the term rarely extends to a tier beneath the highest division. A contrast is implied, with certain electoral districts or narrower divisions. It can be given to the associated territory, if any, to denote its undivided nature, in a specific context. Unambiguous synonyms are the prefixes of cross-, all- or whole-, such as cross-membership, or all-state.
Multi-member constituencies existed in the Parliament of the United Kingdom and its predecessor bodies in the component parts of the United Kingdom from the earliest era of elected representation until they were abolished by the Representation of the People Act 1948. Since the 1950 general election, all members of the House of Commons have been elected from single-member constituencies.
Panachage is a mixed single vote variant of list proportional representation. In panachage, voters support individual candidates. Voters have multiple votes, which they can split between individual candidates in different party lists. Seats are allocated to each party based on the number of votes for all of its candidates. Seats allocated to a party go to that party's most-popular candidates.
Plurality block voting is a type of block voting method for multi-winner elections. Each voter may cast as many votes as the number of seats to be filled. The candidates with the most votes are elected. The usual result when the candidates divide into parties is that the most-popular party in the district sees its full slate of candidates elected, even if the party does not have support of majority of the voters.
Instant-runoff voting is a single-winner, multi-round elimination rule that uses ranked voting to simulate a series of runoff elections. In each round, the candidate with the fewest first-preferences is eliminated. This continues until only one candidate is left. Instant runoff falls under the plurality-with-elimination family of voting methods, and is thus closely related to rules like the two-round runoff system.
An electoral or voting system is a set of rules used to determine the results of an election. Electoral systems are used in politics to elect governments, while non-political elections may take place in business, non-profit organisations and informal organisations. These rules govern all aspects of the voting process: when elections occur, who is allowed to vote, who can stand as a candidate, how ballots are marked and cast, how the ballots are counted, how votes translate into the election outcome, limits on campaign spending, and other factors that can affect the result. Political electoral systems are defined by constitutions and electoral laws, are typically conducted by election commissions, and can use multiple types of elections for different offices.
A winner-take-all electoral system is one where a voting bloc can win all seats in a legislature or electoral district, denying representation to any political minorities. Such systems are used in many major democracies. Such systems are sometimes called "majoritarian representation", though this term is a misnomer, as most such systems do not always elect majority preferred candidates and do not always produce winners who received majority of votes cast in the district, and they allow parties to take a majority of seats in the chamber with just a minority of the vote.
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