The 2014 campaign secured a second four-year term for Santos.
Colombia's electoral authorities have opened an investigation into whether former Colombian President Juan Manuel Santos accepted illegal campaign contributions from Brazilian construction Odebrecht in 2014.
Renato Rafael Contreras from the Democratic Center, Doris Méndez Cubillos from Santos' Liberal Party and human rights lawyer Luis Guillermo Pérez were the three judges of the National Electoral Council who determined there were enough grounds to proceed to a formal investigation.
They made the decision based on the investigation of the Attorney General's Office, "in order to determine whether there were new elements that could be investigated," said the judges in a statement.
They convoked Santos on Oct. 4 to give his version of the allegations against him.
According to Colombian daily La Semana, the CNE's investigation is following new documents transferred in March from the Attorney's Office that had not been taken into account so far. According to the documents, the funds Odebrecht sent to Santos' campaign went through the firm Gistic Soluciones.
In June, Colombian lawmakers decided to launch a similar investigation, based on journalist Vicky Davila's published interview with former Sen. Bernardo Miguel Elias Vidal, popularly known as "Ñoño" Elias, now serving time in prison for his part in the Odebrecht scandal.
Arrested on August 2017, Elias eventually pleaded guilty to charges that he and his political allies accepted nearly 17 billion pesos (some US$6.5 million) in bribes in 2012 to ensure that a lucrative highway contract went to Odebrecht.
The head of Santos' successful 2014 re-election campaign, Roberto Prieto, was sentenced to five years in prison for taking money from Odebrecht.
Odebrecht and its petrochemical unit, Braskem, agreed in December 2016 to pay at least US$3.5 billion to resolve charges with authorities in the United States, Brazil and Switzerland arising out of their schemes to pay hundreds of millions of dollars in bribes to government officials around the world.
Odebrecht, which admitted in the settlement that the scheme began as early as 2001, was initially believed to have paid US$11 million in bribes in Colombia to win public-works contracts.
But Colombian Attorney General Nestor Humberto Martinez said in July 2017 that corrupt officials in the Andean nation in fact received a total of US$27 million in bribes from the Salvador, Brazil-based engineering giant.