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The Brazilian municipal elections of 2012 took place on October 7 and on October 28 (for cities with more than 200,000 voters, where the second round is available). Over 138 million voters chose mayors, deputy mayors and city councillors for the 5,568 municipalities of Brazil. These were the first elections in which the recently registered parties Partido Pátria Livre (PPL) and Partido Social Democrático (PSD) participated; they were both recognized by the Superior Electoral Court (Tribunal Superior Eleitoral – TSE) in 2011. Political parties whose candidates wished to run for the 2012 elections had to be registered at the TSE for at least one year before the election date, while candidates also had to be affiliated to a party for the same period of time. Conventions for the selection of candidates within the parties occurred between 10 and 30 June, while the registry of candidates and alliances with the Regional Electoral Courts (Tribunais Regionais Eleitorais – TREs) took place until July 5. Electoral campaign was authorized from the moment a candidacy had been registered. The free electoral program (propaganda eleitoral gratuita) – two daily slots on free-to-air TV and radio for political advertising paid by the Electoral Justice fund – ran weekdays from 21 August until 4 October. According to the current Brazilian electoral law, the two-round system – should the leading candidate receive less than 50% +1 of the votes – is only available for cities with more than 200,000 voters. This includes all state capitals, with the exception of Boa Vista, Roraima and Palmas, Tocantins, plus 59 other municipalities. The free electoral program for the second round ran from 13 October until 26 October.
Below is a list of the cities where the runoff took place (bold denote state capitals). These cities are home to 31 725 967 of the country's total constituency of 140 646 446 registered electors; that is, 22.56% of Brazilian voters went to the polling stations on October 28.