Breaking News Emails

Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.

Colombian President Juan Manuel Santos won a second term on Sunday with an election victory that allows him to continue peace talks with Marxist guerrillas to end a half-century war.

Santos beat right-wing challenger Oscar Ivan Zuluaga with about 50.9 percent support after a bitter campaign that challenged voters to decide between the incumbent's pursuit of negotiated peace or a likely escalation of combat under his rival.

Zuluaga won about 45 percent support. Votes had been counted from more than 99 percent of polling stations, meaning Santos' victory was secure.

Sign up for breaking news alerts from NBC News

At his campaign headquarters in Bogota, supporters danced and waved flags as music blared and confetti rained down. Raising their hands daubed with the words "peace", followers waited for Santos to take to the stage to proclaim victory.

In an old industrial part of the city, close to Bogota's colonial center, some of Zuluaga's deflated backers sobbed as they watched the final numbers roll in.

Santos' re-election comes as a relief to his backers as well as traditional rivals from the left who backed the peace talks and feared they could have been jettisoned by Zuluaga in favor of trying to end the long conflict on the battlefield.

President Juan Manuel Santos casts his vote in Bogota June 15, 2014. Colombians voted on Sunday in the tightest presidential election in decades, a contest that will decide if the nation moves ahead on peace talks with Marxist FARC rebels or step up its battlefield offensive to end a 50-year war.JOSE MIGUEL GOMEZ / Reuters

Santos, a center-rightist who hails from one of the country's most influential families, opened talks with rebel leaders of the Revolutionary Armed Forces of Colombia (FARC) in late 2012, aiming to end a conflict that has killed over 200,000 people and forced millions more from their homes.

He made hopes of peace his key selling point throughout the campaign.

"I voted for peace, Santos is a decent man who has shown another way of doing politics," said Wilmar Diaz, a 35-year-old public relations executive.

Although they have shown more progress than previous failed efforts, the peace talks in Cuba have been divisive. Zuluaga supporters fear a peace deal could hand FARC leaders political power without punishment for their crimes.

Santos sought to capitalize on support for the negotiations by revealing in the last days of the campaign that preliminary talks had begun with the country's second biggest rebel group, the National Liberation Army (ELN).

A victory for Zuluaga, 55, could have spelled the end of the peace process if the FARC rejected the tougher conditions he vowed to impose to keep talks going.

- Reuters