Cumulative voting

Cumulative voting (accumulation voting or weighted voting) is a multiple-winner voting system intended to promote proportional representation. It is used heavily in corporate governance, where it is mandated by many U.S. states, and it was used to elect the Illinois House of Representatives from 1870 until 1980.

In this system, a voter facing multiple choices is given X number of points. The voter can then assign his points to one or more of the choices, thus enabling one to weight one's vote if desired. This form of voting is advocated by those who argue that minorities deserve more representation, and thus could be assigned more points per voter.

Unlike preference voting where the numbers represent ranks of choices or candidates in some order (i.e. they are ordinal numbers), in cumulative votes the numbers represent quantities (i.e. they are cardinal numbers).

This describes how cumulative voting works in a single case. Where there is a General Election, several cases occur simultaneously in different constituencies. There is no automatic requirement that all of these should return the same numbers of winners under all implementations; indeed certain demographic rules for boundary changes might alter the number of winners as well as, or instead of, the boundaries. So the special case of one single winner is possible; this is mathematically identical to First-past-the-post-election-system voting.