Bogotá, May 19 (RHC) -- Colombia's presidential election campaign closed Sunday, a week before voters are scheduled to cast their ballots on May 25th.

Incumbent President Juan Manuel Santos called on Colombians to vote for him if they want to see the country at peace, after his administration began a peace process with FARC guerrillas in 2012.

Santos, who up to recent days had led election polls, has based his election campaign on the future success of the peace talks with the FARC rebels. However, latest surveys have seen the far-right candidate, Oscar Ivan Zuluaga, narrow Santos' advantage to virtually nothing.

Zuluaga's rise in popularity puts the peace talks at risk, as he has threated to end them if he wins the presidential seat. Zuluaga also made headlines last week, after Semana magazine revealed a video showing the candidate meeting an illegal hacker.

Other presidential hopefuls include the Green Party candidate Enrique Penalosa; the left-wing Polo Democratic candidate Clara Lopez; and the Conservative Party's Marta Lucia Ramirez.

Penalosa ended his campaign with a bike ride through the Colombian capital city of Bogota, where he called on Zuluaga to renounce his candidacy over the video scandal, claiming Zuluaga lied to the country when he said he had no connection with the illegal hacker.

Lopez asked the courts to "do their job" and investigate cases of illegal infiltration by Zuluaga's campaign and alleged drug money in Santos's campaign back in 2010.

Ramirez ended her campaign among crowds in the city of Ubate, located in the central Cundinamarca department, where she sought support from Colombians in a bid to become the country's first woman president.

Candidates are now preparing for a series of public debates scheduled for the coming week after which Colombians will decide who will lead the Andean country until 2018.