Multi-party state

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. Apart from one-party-dominant and two-party systems, 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, Belgium, Brazil, Croatia, 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, Switzerland, 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 are compelled to form compromised coalitions for the purpose of developing power blocks and attaining legitimate mandate.

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