By Julia Symmes Cobb and Luis Jaime Acosta
BOGOTA (Reuters) - Spying and bribery allegations have marred the run-up to Colombia's presidential election with top advisors for both candidates resigning in a bitter campaign that could sour voter support just over two weeks from the ballot.
Both President Juan Manuel Santos and his closest rival Oscar Ivan Zuluaga have been tarnished by mud-slinging between their camps, shifting attention in an election that was on track to be a referendum on the peace process with Marxist-led rebels.
Zuluaga, who represents the new Democratic Center party, is a staunch opponent of the negotiations in Havana, Cuba that Santos opened 18 months ago with the Revolutionary Armed Forces of Colombia, or FARC.
Frontrunner Santos' campaign chief, Venezuelan political strategist Juan Jose Rendon, resigned this week after claims made in testimony by an indicted drug trafficker that Rendon received $12 million to smooth the way for the trafficker and several associates to avoid extradition to the United States.
Two days later, Zuluaga's campaign chief, Luis Alfonso Hoyos, quit as a hacking scandal erupted appearing to connect him to efforts to hobble talks with the FARC.
Then former President Alvaro Uribe, a one-time Santos ally now backing Zuluaga, said he had evidence that Santos' 2010 presidential campaign used $2 million of the money Rendon purportedly received to pay off campaign debts.
The trading of allegations is relegating campaign proposals to the background and could reshape the political fortunes of the candidates in the first round on voting on May 25.
"In this campaign we really haven't heard much about the candidates' proposals, just the scandals and the attacks between them," said Angela Baron, 43, an oilfield engineer.
"It just shows the low level of our politics."
Opinion polls put Santos and Zuluaga ahead in the first round, but neither is able to pull off enough votes to avoid a runoff on June 15.
"This will influence the vote considerably," said political analyst Alejo Vargas. "The common citizen unfortunately is inclined to vote based on feelings and sympathies."
Other candidates in the field could benefit or the scandals may lead to more absenteeism, which analysts are already predicting will be high.
"ENEMIES OF PEACE"
Both campaigns have called for investigations into the other, while denying they had knowledge of illegal activity.
Rendon, a critic of the socialist government in Venezuela, denied taking any money, but quit to prevent what he described as "enemies of peace" tarnishing Santos and the election campaign of his U party coalition.
Santos has backed Rendon and said his former advisor told him that the traffickers made contact but that no deal was reached because the men refused to turn themselves in.
The drug dealers have since been jailed.
While the Santos camp battles bribery allegations, the Zuluaga campaign faces allegations that a contractor in its social media team spied on the communications of peace negotiators and possibly hacked into the president's email.
The contractor, Andres Sepulveda, has been arrested and charged with espionage, data interception and use of malicious software. The prosecution service, which detained Sepulveda on Tuesday, said there were "initial indications" that Santos' emails had also been monitored.
The timing of the arrest - a day after Rendon's departure - was called into question by Zuluaga, who implied that the chief prosecutor's office is allied with Santos.
Critics of Zuluaga and Uribe have pointed out that Uribe's time in office was also marred by spying scandals, when journalists, magistrates and politicians were followed and eavesdropped on by intelligence agents.
(Editing by Helen Murphy and Grant McCool)