Electoral system

An electoral system is the set of rules and procedures governing how votes are cast, counted, and translated into elected offices or legislative seats. Its design shapes representation, competition, and the incentives facing voters and candidates.

Electoral district: A geographic area whose voters elect one or more representatives. District magnitude determines how many seats each area fills.
First-past-the-post voting: A single-winner rule in which the candidate with the most votes wins, without needing a majority. It converts each district's largest vote total directly into its sole seat.
Proportional representation: A family of electoral systems designed to make parties' seat shares correspond broadly to their vote shares. It prioritizes proportional outcomes over winner-take-all results.
Duverger's law: A political science proposition linking plurality elections in single-member districts to two-party competition. It describes how winner-take-all rules can narrow party competition.
Ballot: A method or document through which voters express electoral choices. Ballot design determines which choices voters can record.
Two-round system: An electoral method that holds a second ballot if no candidate meets the required threshold in the first. A runoff can let voters reconsider after initial preferences are revealed.
Majoritarian representation: A family of electoral systems that awards representation to candidates or parties winning majorities or pluralities. It favors decisive winners and often links representatives to local constituencies.
Gerrymandering: The manipulation of electoral district boundaries to advantage a political party or group. District rules can be exploited through strategic boundary drawing.
District magnitude: The number of representatives elected from a district in one election. It strongly affects how proportional a system can be.
Instant-runoff voting: A single-winner method that eliminates the lowest-ranked candidate and transfers ballots until one remains. It uses ranked ballots to simulate successive elimination rounds.

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