Petro succeeds the unpopular conservative Iván Duque, who was not allowed to stand for a new round due to the country’s election laws.
At his side as vice president, Petro will have 40-year-old Francia Márquez, who will be the country’s first black woman in office.
Button margin
When over 99.5 percent of the votes have been counted after the second round, Petro has 50.5 percent of the votes against opponent Rodolfo Hernández 47.3 percent, a margin of about 700,000 votes.
– I hope that Mr. Gustavo Petro knows how to govern the country and is faithful to his rhetoric against corruption, says Hernández in a live broadcast on Facebook.
In the first round of the presidential election on May 29, neither Gustavo Petro nor Rodolfo Hernández won enough votes for a direct decision, and before the second round, the candidates have practically been side by side in the opinion polls.
Been mayor
The 62-year-old senator Gustavo Petro was mayor of the capital Bogotá 2012-2015 and has tried to become president twice before. He used to belong to the (now disbanded) guerrilla group M-19. Now he is a self-proclaimed fighter for the indigenous people and other vulnerable people. In the first round of elections, he received just over 40 percent of the votes.
77-year-old Hernández – who has been compared to the US President Donald Trump, a businessman who came from nowhere and with establishment-critical rhetoric knocked out all other right-wing candidates – then received 28 percent.