Colombia election runoff

A girl waves Colombian national flags as supporters of President Juan Manuel Santos celebrate after results indicated that he won Sunday's runoff election. (Guillermo Legaria / AFP/Getty Images / June 15, 2014)

Colombian President Juan Manuel Santos appeared headed for a reelection victory Sunday in a runoff against former Finance Minister Oscar Ivan Zuluaga, according to early returns.

With 88% of votes counted, Santos had 50.7% of the vote versus 45.1% for his challenger. Zuluaga was the top vote-getter in the first round of voting May 25.

In Sunday's balloting, the incumbent was riding a surge of support in the capital, Bogota, where he reversed his poor first-round showing to outpoll Zuluaga by more than 200,000 votes.

Santos had framed his candidacy as one for peace versus continued conflict if Zuluaga wins. The president initiated negotiations with the Revolutionary Armed Forces of Colombia, or FARC, rebel group in Havana in November 2012 in a bid to end a half-century-long civil conflict.

After a poor showing in the first round in May, Santos attracted endorsements from various labor unions, businesses and intellectuals touting the peace initiative. He also won support from two losing first-round candidates, former Bogota Mayors Clara Lopez and Enrique Penalosa.

Zuluaga had criticized the peace negotiations as conceding too much to FARC and said he opposed giving the rebels congressional representation and impunity for past crimes, two likely prerequisites of a peace deal.

Kraul is a special correspondent.