Democratic Electoral Systems

A set of 30 vocabulary-style flashcards covering democratic electoral systems, specific models like SMP and STV, and their effects on political parties and representation.

Majoritarian Electoral Systems

Electoral systems where the winner gets everything based on contesting each legislative seat separately in a winner-take-all format.

Proportional Electoral Systems

Systems where seats are awarded to political parties in a bloc roughly proportional to their share of the total vote.

Single Member Plurality (SMP)

A majoritarian model where the winner is the candidate with a plurality of votes in a single-member district.

Plurality

A voting outcome where a candidate wins by receiving more votes than any other candidate, though not necessarily a majority (over $50\%$).

Single Member Majority (SMM)

An electoral system where a candidate must win a majority of votes in a single-member district to be elected, often involving a two-round runoff.

Two Round Runoff

A feature of SMM systems where a second election is held between top candidates if no one attains a majority in the first round.

Alternative Vote / Instant Runoff

A system where voters rank candidates, and the weakest are eliminated with their votes recast until one candidate achieves over $50\%$.

Duverger’s Law

The principle stating that the presence of single-member districts leads to a two-party system.

Strategic Voting

A behavior in majoritarian systems where voters choose a candidate based on their likelihood of winning rather than purely on personal preference.

Multi-member districts

Electoral districts where more than one person is elected to the legislature, a necessary component of proportional systems.

Party List Voting

A proportional system where voters choose a party's ranked list, and the party is allocated seats based on its share of the vote.

Threshold

The minimum percentage of the vote, usually between $3-5\%$, that a party must meet to gain seats in a proportional system.

Single Transferable Vote (STV)

A proportional model where voters rank candidates in multi-member districts and seats are awarded using a quota system.

Quota System

A mathematical threshold used in STV to determine the number of votes required for a candidate to win a seat.

Single Non-Transferable Vote (SNTV)

A mixed system where voters in multi-member districts cast a single vote for one candidate, and those with the most votes win.

Plurality Block Voting

A system where voters in multi-member districts cast several votes equal to the number of seats, often allowing one party to sweep all seats.

Mixed Member Majority (MMM)

An electoral model where some seats are elected via SMP and others via proportional systems (Party List or STV) through two separate votes.

Mixed Member Proportional (MMP)

A system where voters have two votes (one SMP, one proportional) and final seat allocation is adjusted so the total result reflects the proportional vote.

Lisa Murkowski

A candidate who won the $2010$ Alaska Senate seat as a write-in candidate with a plurality of $39.49\%$ of the vote.

French Presidential Election of 2002

An example of an SMM system where low turnout in the first round occurred because results involving $16$ candidates were believed to be predictable.

Italy’s Chamber of Deputies (2006)

An election held under a fully proportional party list system where a low $3\%$ threshold resulted in thirteen parties gaining seats.

Candidate-based systems

Elections, typically majoritarian, where votes are cast for individuals rather than parties, leading to stronger candidates and weaker parties.

Party-based systems

Electoral systems, such as proportional models, where political parties are the primary focus and individual candidates have less independent power.

Winner-take-all

The core concept of majoritarian elections where one winner takes the seat and all other candidates receive nothing.

Local representation

A primary advantage of SMP, SMM, and Instant Runoff systems, ensuring a specific geographic area has its own legislator.

Heterogeneity

State-wide diversity that can lead to majoritarian systems having more than two major parties despite Duverger's Law.

Recasting

The process in Instant Runoff or STV where votes from eliminated candidates (or surplus votes) are moved to the voter's next ranked choice.

Governing Coalition

A group of multiple political parties that join together to rule, often seen in proportional systems like Italy's $2006$ parliament.

Disproportionality

An effect where the percentage of seats won does not match the percentage of votes received, often expanded in Block Voting districts.

Proportionality

The degree to which the distribution of seats in a legislature matches the distribution of the popular vote as expressed by citizens.