Two-round system

The two-round system (also known as the second ballot, runoff voting or ballotage) is a voting system used to elect a single winner where the voter casts a single vote for their chosen candidate. However, if no candidate receives the required number of votes (usually an absolute majority or 40–45% with a winning margin of 5–15%), then those candidates having less than a certain proportion of the votes, or all but the two candidates receiving the most votes, are eliminated, and a second round of voting is held.

The two-round system is used around the world for the election of legislative bodies and directly elected presidents. For example, it is used in French presidential, legislative, and departmental elections. In Italy, it is used to elect mayors, but also to decide which party or coalition receives a majority bonus in city councils. A two-round system is used also to elect the presidents of Afghanistan, Argentina, Austria, Benin, Brazil, Bulgaria, Burkina Faso, Cape Verde, Chile, Colombia, Costa Rica, Croatia, Czech Republic, Cyprus, Dominican Republic, Ecuador, Egypt, El Salvador, Finland, Ghana, Guatemala, Haiti, India, Indonesia, Liberia, Peru, Poland, Portugal, Romania, Senegal, Serbia, Slovakia, Slovenia, Timor-Leste, Turkey, Ukraine, Uruguay and Zimbabwe – see: Table of voting systems by nation. Historically it was used in the German Empire of 1871–1918, in New Zealand in the 1908 and 1911 elections, and in Israel to elect the Prime Minister in the 1996, 1999 and 2001 elections.

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