Low voter turnout in Colombia means runoff for President Santos and conservative rival

A possible peace deal with Marxist rebels hangs in the balance as Colombians prepare for three more weeks of rancorous campaigning after an ally of conservative former President Alvaro Uribe won the most votes in the first round of presidential voting.

Oscar Ivan Zuluaga, a former finance minister, won 29 percent of the votes cast Sunday, stealing the momentum from President Juan Manuel Santos, who garnered 26 percent. Without the 50 percent needed to win outright, the two will face off again June 15 after finishing atop a field of five candidates.

Relentless attacks in the campaign's final stretch and the arrest of an adviser on charges of spying appeared not to have eroded support for Mr. Zuluaga, who had emerged as President Santos' toughest challenger thanks to the backing of his one-time boss and mentor, the still-popular Mr. Uribe.

Despite all the advantages of running as an incumbent, Santos limped to the finish line Sunday, not even taking his hometown of Bogota. One powerful ally, Sen. Roy Barreras, told The Associated Press that the second-place finish came like a "bucket of cold water."

Santos framed the runoff as a battle between the "fear and hope," foreshadowing what is likely to be dogfight over the future of the current peace talks with Colombia's biggest rebel movement and Uribe's polarizing legacy of a no-holds-barred military offensive against the guerrillas during his 2002-10 administration.

"The choice is between those of us who want to put an end to the war and those who want a war without end," Santos, 62, told supporters in Bogota, who responded with shouts of "Peace for Colombia!"

As Uribe's defense minister and now president, Santos is credited with handing the rebels some of their biggest battlefield defeats, but he took a risk and made the peace negotiations initiated 18 months ago with the Revolutionary Armed Forces of Colombia, or FARC, the centerpiece of his campaign.

Concerns that rebel leaders, on the ropes after a decade-long US-backed offensive, will not be punished for any crimes have been fueling mistrust of the negotiations. Although Zuluaga said he also favors a negotiated settlement, he's also threatened to end talks, saying that if elected he would give FARC negotiators a week to demonstrate their commitment to peace by declaring a permanent cease-fire.

Zuluaga, speaking to supporters without Uribe in an attempt to step out from under the former president's shadow, vowed to put an end to "terrorism" and called the FARC the "world's biggest drug cartel."

"We can't let the FARC pretend to command the country from Havana," he said while reading from prepared remarks.

'Puppets' and 'respect'

But those policy differences were largely swamped in the past two weeks by a string of bitter attacks and startling revelations.

It began with media reports that Santos' campaign manager, J.J. Rendon, received $12 million from the nation's biggest drug traffickers to help negotiate their surrender. Rendon quickly resigned after acknowledging he interceded in the case, though he denied taking any money.

Meanwhile, Zuluaga's campaign came under fire after a computer expert who worked for him was arrested for allegedly hacking into the emails of the president and FARC negotiators.

Zuluaga denounced the arrest as a desperate ploy to derail his campaign. But the emergence of a clandestinely shot video in which Zuluaga listened as the computer expert outlined his strategy to undermine the peace talks cast doubt on the candidate's claim that he had no knowledge of the consultant's alleged activities.

The tensions came to a head in a feisty exchange at a televised debate where Santos accused his rival of being Uribe's "puppet" and Zuluaga fired back: "You must show me respect."

None of the three other candidates were able to capitalize on the last-minute feuding, with Conservative Party candidate Marta Lucia Ramierz coming in third far behind the front-runners, with less than 16 percent of the votes.

The rancor may have disgusted many voters, however. Only 40 percent of the 33 million eligible voters bothered to cast ballots, producing Colombia's lowest turnout in decades.

Bogota-based political analyst Pedro Medellin said that for Santos to pick up lost ground to Zuluaga, he will have to tack further to the left.

One place the president is already looking is the Democratic Pole party, one of the strongest supporters of a peace talks and whose presidential candidate, Clara Lopez, finished a whisker behind Ramirez.

But signing a peace agreement didn't even rank among the top five concerns of voters in a recent Gallup poll, and in focusing on the talks Cuba, Santos risks losing support among many working class Colombians who haven't benefited as much from the country's recent economic boom.

The most recent poll taken 10 days before Sunday's voting showed Santos and Zuluaga locked in a virtual tie in an eventual head-to-head race.