Colombia's electoral system has been riddled with fraud since President Juan Manuel Santos came into office, warns presidential candidate Gustavo Petro, of the Progressive Movement.
The Colombia Humana representative closed his campaign speech by calling attention to how the president denied the European Union Electoral Technical Commision access to voter registry software.
Petro called on supporters to prevent any foul play when the nation heads to the polls on May 27: "We are going to defeat the fraud of Santos and the National Civil Registry in favor of Vargas by registering 100,000 electoral witnesses in Petro.com.co."
The National Electoral Council has, however, agreed to allow observers from the International Foundation for Electoral Systems (IFES) monitor the elections.
The decision was announced after voters complained about the National Civil Registry's failure to patch security flaws which led to the elimination of hundreds of thousands of votes in the 2014 congressional elections.
This year, during the March 11 legislative elections, there were several reports of irregularities, including people casting their vote using photocopies because the registry had failed to print enough official ballots. There were also allegations of vote buying outside polling stations.
According to a new poll released on Friday by Datexco, right-wing candidate Ivan Duque has 36.4 percent of the intended vote; Petro has 31.8 percent, and Sergio Fajardo is trailing with 16 percent.