1958 Chilean presidential election

Presidential elections were held in Chile on 4 September 1958. The result was a victory for Jorge Alessandri, who ran as an independent. Allende's defeat has been commonly attributed to Antonio Zamorano, also known as "Cura de Catapilco", entering the race as a populist left-wing candidate and taking votes from Allende's electorate. This explanation has been questioned by modern research that infers Zamorano took votes from across the political spectrum. The "Catapilco" effect remains a trope in Chilean electoral discourse used to indicate a candidate that finishes third and is believed to have hindered the runner-up.

Electoral system
The election was held using the absolute majority system, under which a candidate had to receive over 50% of the popular vote to be elected. If no candidate received over 50% of the vote, both houses of the National Congress would come together to vote on the two candidates that received the most votes.