Law-and-order President Alvaro Uribe was headed for a landslide victory Sunday in Colombia's most peaceful elections in years, according to partial results, strengthening the US ally's mandate to crack down on armed groups and drug traffickers. A win by the Harvard-educated Uribe would be the first time in more than a century that an incumbent Colombian leader has been elected to a second term and would buck a recent trend toward left-leaning leaders taking office across South America. With nearly 20 percent of the votes counted from Sunday's election, Uribe had 61.2 percent of the vote, surpassing the 50 percent needed for a first-round victory, election officials said. In second place with 22.2 percent was Sen. Carlos Gaviria of the leftist Alternative Democratic Pole party. In third place was Horacio Serpa of the century-old Liberal Party with 12.7 percent.