Party and Electoral Systems and Citizen Organizations
What the exam is asking
This domain links electoral rules to party systems and to interest aggregation by parties, unions, and NGOs. Know the families: single-member district/plurality (SMD), proportional representation (PR), and mixed systems. Expect Duverger's law: SMD tends toward two-party competition; PR tends toward multiparty systems.
Map the cases. The UK uses SMD (first-past-the-post), producing Conservative–Labour dominance with regional parties. Russia uses mixed and PR elements but manages competition to favor United Russia. Mexico uses a mixed system with PR seats; the PRI dominated for decades before pluralization. Nigeria uses SMD in a multiethnic federation, encouraging regional and patronage-based parties. Iran holds elections but the Guardian Council screens candidates, so party competition is constrained. China is a one-party system where the Communist Party aggregates interests internally.
Traps
- Assuming PR always means fragmentation; thresholds and district size matter.
- Forgetting that electoral rules are chosen strategically by incumbents to shape outcomes.
- Confusing interest groups with parties - groups aggregate demands, parties contest power.
- Overlooking corporatism (state-structured interest representation) versus pluralism.
Rule of thumb
Trace the chain: electoral rule → seat allocation → number of viable parties → coalition or single-party government. Each arrow is a testable link.
Worked example
Question: Why does the UK typically produce single-party majorities? Because plurality rule in single-member districts rewards the largest party with a seat bonus and penalizes dispersed third parties - Duverger's law in action.