ABSTRACT
Chapter 2 explores Duverger’s Law, or the argument that single-member plurality electoral systems (SMP), like the one used in the United States, favor the two-party system, including because voters want to avoid wasting their votes. The chapter demonstrates through an analysis of elections in fifty countries that third parties are generally weaker in SMP systems than in proportional representation systems. However, the chapter also suggests through a district-level analysis of elections in Australia, Canada, India, the UK, and the United States that voters are not avoiding wasting their voters. It also shows that the vote for third parties is substantially lower in the United States than other countries with SMP electoral systems.
