Leftist frontrunner Luisa Gonzalez looked set to take on a surprise candidate, the youthful son of one of Ecuador's richest men, in a run-off election in October, official results showed Sunday.
Gonzalez, a lawyer close to divisive former socialist president Rafael Correa, was leading with 33 percent of the vote, as 80 percent of the vote was counted.
President of the National Electoral Council Diana Atamaint said results showed no candidate had hit the threshold to win outright, after a tense day of voting under heavy security.
"We are heading to a second round election on October 15," she told journalists.
Gonzalez will likely go head to head with Daniel Noboa, 35, who had 24 percent of the vote despite not figuring as a favorite in opinion polls ahead of a chaotic election marred by the assassination of a serious contender.
"We are making history," Gonzalez said, hailing her "triumph" in the first round. Noboa, said the "youth" had chosen him to beat Correa's party.
The run-off election is set for October 15, and the stakes are high in a once-peaceful nation engulfed by drug violence.
The small South American country has in recent years become a playground for foreign drug mafias seeking to export cocaine from its shores, stirring up a brutal war between local gangs.
The murder of serious presidential contender Fernando Villavicencio on the campaign trail just 11 days before the vote underscored the challenges facing the country.
Ecuadorans voted for a successor to conservative leader Guillermo Lasso, who called a snap election to avoid an impeachment trial just two years after coming to power.
Soldiers and police searched voters at the entry to polling stations, while some of the eight presidential candidates wore helmets and bulletproof vests to cast their ballots.
"The most serious problem is insecurity," said voter Eva Hurtado, 40, as she left a polling station north of the capital Quito on Sunday morning. "So many crimes, assassinations, disappearances. We are afraid."
"Security, above all the security of our families, of our people, must be improved," said public worker Luis Veloso, 52.
- Amazon referendum -
Gonzalez, who sees herself as a defender of Correa's socialist legacy, had long been leading opinion polls, with Villavicencio second until his murder.
She has said the former president Correa will be a close advisor if she is elected.
Correa was sentenced to eight years in jail after an investigation by Villavicencio into corruption, and fled to Belgium where he has been living in exile for six years.
Villavicencio was replaced at the last minute by a close friend and another journalist, Christian Zurita, who came in third with 16 percent of votes.
Hours ahead of the vote, Zurita said he was receiving death threats on social media.
However Noboa, who appeared in the only televised debate in a bulletproof jacket, pulled off the big surprise of the day.
His father, Alvaro Noboa, ran unsuccessfully for the presidency five times.
In one of the world's most biodiverse countries, a historic referendum also took place on whether to keep drilling for oil in an Amazon reserve that is home to three of the world's last uncontacted Indigenous populations.
With only 30 percent of votes counted, the "yes" vote to halt drilling was leading with 58 percent of support.
- Brutal gang war -
Ecuador was once seen as a haven of peace wedged between cocaine-producing nations Colombia and Peru.
The small country straddles the Andes and the Amazon, and was best known as the world's top exporter of bananas and home to the biodiverse Galapagos Islands, where British scientist Charles Darwin developed his theory of evolution.
However, in the past five years its large ports, lax security and corruption have lured foreign cartels that have come under increased pressure from the war on drugs in Mexico and Colombia.
A struggle for power between local gangs has mostly played out in prisons, where 430 have been killed since 2021, leaving a trail of dismembered and burned bodies.
In 2022, the country hit a record of 26 murders per 100,000 inhabitants, higher than the rate in Colombia, Mexico or Brazil.
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