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Plurality block voting

Non-proportional electoral system

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  • 5 chapters

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Through Electoral district, First-past-the-post voting and Coalition

The term plurality at-large is in common usage in elections for representative members of a body who are elected or appointed to represent the whole membership of the body (for example, a city, state or province, nation or country, club or association). (The plurality at-large election system is common in cities. The Senate of the Philippines is elected by the rare country-wide use of block voting.) Where the system is used in a territory divided into multi-member electoral districts, the system is commonly referred to as "block voting" or the "bloc vote". These systems are usually based on a single round of voting.

The party-list version of block voting is party block voting (PBV), also called the general ticket, which also elects members by plurality in multi-member districts. In such a system, each party puts forward a slate of candidates, a voter casts just one vote, and the party winning a plurality of votes sees its whole slate elected, winning all the seats; and is thus distinct from plurality block voting.

Casting and counting ballots

Block voting

In a block voting election, all candidates run against each other for m number of positions, where m is commonly called the district magnitude. Each voter selects up to m candidates on the ballot. Each of the voters have m votes, and are able to cast no more than one per candidate. They cannot vote for the same candidate more than once, as is permitted in cumulative voting.

Voters are permitted to cast their votes across candidates of different parties (ticket splitting).

The m candidates with the most votes (who may or may not obtain a majority of available votes or support from the majority of the voters) are declared elected and will fill the positions.

Due to multiple voting, when a party runs more than one candidate, it is impossible to know if the party had support of as many voters as the party tally of votes (up to number of voters participating in the election) or if it had support of just the number of voters equivalent to the votes received by the most popular candidate and the other candidates of that party merely received votes from subset of that group.

Example

Candidates are running in a three-member district; each of the 10,000 voters may cast three votes (but do not have to). Voters may not cast more than one vote for a single candidate.

Party A has about 35% support among the electorate, Party B around 25% and the remaining voters primarily support independent candidates.

Candidates of Party A won in a landslide, even though they only received a plurality (35–37%) among the voters (10,000). This is because most parties run as many candidates as there are open seats and voters of a party usually do not split their ticket, but vote for all candidates of that party.

By contrast, a single transferable vote system would likely elect 1 candidate from party A, 1 candidate from party B and 1 independent candidate in this scenario.

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