On Nov. 22, Mauricio Macri defeated Daniel Scioli in a presidential runoff. Marci received 51.4% of the vote. Scioli received 48.6%. The runoff came after the two candidates tied in October. Because of the tie, Argentina used its ballotage system, which doesn't require candidates to win by more than 50% of the vote.
The ballotage system had been in the country's Constitution since a 1994 amendment. A member of the Republican Proposal party, Marci became Argentina's first non-radical or non-Peronist party president since 1916. He took office on Dec. 10, 2015.