BOGOTA, Colombia

Ecuadorians do not yet know who will run in a runoff presidential election, four days after voting was conducted.

With 99% of votes counted, it appears right-wing former banker Guillermo Lasso will run in the second round against left-wing economist Andres Arauz. But the race remains too close to call.

Arauz won the elections with a comfortable lead but was short of the 40% threshold needed to avoid a run-off on April 11.

He secured 32.6% of the vote to Lasso’s 19.7%. Indigenous candidate and lawyer Yaku Perez is third with 19.5%.

The battle for second place has kept the country in suspense and raised questions about the fairness of the electoral process.

Perez appeared in third place in almost all polls, far behind Arauz and Lasso, who were said to be the frontrunners.

Yet, the Indigenous candidate was likely to enter the race in the second round until the scales shifted in the conservative candidate´s favor Wednesday, which caused talk of election fraud.

The Pachakutik party, the political arm of Ecuador's largest indigenous organization, called for demonstrations in Quito and other cities to defend the Perez’s numbers.

"[Former President Rafael] Correa's supporters are afraid that we will reach the second round,” said Perez. “They know that Guillermo Lasso will be easily defeated, but with us it becomes an uphill battle. It is very difficult for him to beat us.”

Arauz, unknown to most until recently, has the backing of Correa, who stepped down at the end of his third term in 2017 with approval ratings of more than 60%.

Correa, who is living in exile in Belgium, was convicted on corruption charges in April.