BOGOTA Juan Manuel Santos, a former defense and finance minister, won Colombia's presidency by a landslide on Sunday, handing him a strong mandate to tackle tasks from a stubborn deficit to tense ties with Venezuela.
Santos succeeds President Alvaro Uribe as the leader of Washington's top ally in South America and has vowed to continue pro-business policies that saw foreign investment soar and a popular tough line against leftist FARC rebels.
Santos won 69 percent of the votes in the run-off election against eccentric former Bogota Mayor Antanas Mockus, who won 27 percent by challenging traditional parties with his call for cleaner government.
Uribe steps down in August, still popular after two terms during which he weakened the FARC and disarmed outlawed paramilitaries. Oil and mining investment is booming despite lingering violence from the cocaine-fueled conflict.
The victory by a staunch Uribe ally will be applauded by Wall Street as a continuation of his pro-investment policies and likely will help Colombia's peso, stock market and local TES bonds.
"Now thanks to the security we have, we can focus on prosperity, in creating more jobs, in fighting poverty and generating opportunities for all," Santos told cheering crowds at a victory speech late on Sunday.
Santos easily won a first round on May 30 but fell short of the 50 percent plus one vote needed to avoid a run-off against Mockus, a former university professor.
Santos, who saw Colombia through a fiscal crisis in the 1990s, must deal with double-digit unemployment, a persistent deficit and a costly public health system as the economy recovers from the effects of the global downturn.
A U.S. and British-trained economist, Santos got more than 9 million votes -- a record for a Colombian president -- and will assume the presidency in August with a strong mandate and solid initial support in the Congress.
He has called for a "unity government" and secured backing from the Conservative and Cambio Radical parties and part of the opposition Liberal party. But he may struggle to match the heft of Uribe, who maintained popularity of around 70 percent.
"We do not expect the presidential transition to bring about a noticeable change in the direction of investor friendly macro and financial policies," Goldman Sachs analyst Alberto Ramos said in a report.
"Governability going forward might not be as strong as under the eight years of President Uribe's presidency as no other candidate enjoys such a high level of charisma, political capital, and personal leverage."
Tense ties with Venezuelan President Hugo Chavez will also challenge Santos. Chavez cut trade in a dispute over U.S. involvement in Colombia.
Santos says Chavez and he are "oil and water" but has offered to talk based on mutual respect.
As defense minister, Santos oversaw some of the sharpest blows against the guerrillas. He also ordered a successful operation to rescue prominent hostages held by the FARC, including a former presidential candidate and three American contractors.
But his tenure was tainted by charges troops killed civilians to artificially lift combat tolls. The scandal cost the army chief and 27 officers their posts but Santos said he worked to halt rights abuses within the armed forces.
(Editing by John O'Callaghan)