Multi-party system

A multi-party system is a system in which multiple political parties across the political spectrum run for national election, and all have the capacity to gain control of government offices, separately or in coalition. Multi-party systems tend to be more common in parliamentary systems than presidential systems, and far more common in countries that use proportional representation compared to countries that use first-past-the-post elections.

First-past-the-post requires concentrated areas of support for large representation in the legislature whereas proportional representation better reflects the range of a population's views. Proportional systems have multi-member districts with more than one representative elected from a given district to the same legislative body, and thus a greater number of viable parties. Duverger's Law states that the number of viable political parties is one plus the number of seats in a district.

Argentina, Austria, Brazil, Denmark, Finland, France, Germany, Iceland, India, Indonesia, Ireland, Israel, Italy, Lebanon, Mexico, Moldova, Nepal, the Netherlands, New Zealand, Norway, the Philippines, Portugal, Romania, Serbia, Spain, Sri Lanka, Sweden, Taiwan, Tunisia and Ukraine are examples of nations that have used a multi-party system effectively in their democracies. In these countries, usually no single party has a parliamentary majority by itself. Instead, multiple political parties form coalitions for the purpose of developing power blocks for governing.

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