Ballotage in Argentina

The ballotage system is included in the Constitution of Argentina. It was added by the 1994 amendment, as part of the negotiations between Raúl Alfonsín and President Carlos Menem.

Most countries with a two-round system require a candidate to win at least 50 percent of the vote to win the presidency in a single round. In Argentina, however, a candidate does not need a majority for a first-round victory. Instead, they must win 45% of the vote, or 40% of the vote and a difference of 10% with the runner-up. Lower level Argentine districts, such as the city of Buenos Aires, included the ballotage in their local constitutions, but with the standard requirements.

Since the amended constitution took effect, only two elections have had a result that required a ballotage.

In 2003 elections, Menem took 24.45% of the vote to 22.24% for Néstor Kirchner. However, Menem pulled out of the runoff when polls showed him losing badly to Kirchner, effectively handing the presidency to Kirchner.

The 2015 elections, with both candidates in a tie of nearly 35%, also required a ballotage.

In the first runoff voting ever held for an Argentine presidential election, opposition leader and Buenos Aires Mayor Mauricio Macri narrowly defeated FPV candidate and Buenos Aires Province Governor Daniel Scioli, with the first obtaining 51.34% of the votes and the second receiving 48.66%.

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