President Αlvaro Uribe, popular for reducing crime as part of his crackdown on drug-running leftist guerrillas, is expected to win re-election in May and to carry on his tough, Washington-backed, military and pro-market economic policies.
He urged his countrymen to vote despite a series of recent rebel attacks aimed at scaring people away from the polls.
Juan Carlos Echeverry, chairman of the economics department at the University of the Andes in Bogotα, said he expected that Mr. Uribe would win a working majority in the Senate while lower house results were more uncertain. Mr. Uribe has strong support in both chambers but has struggled to form reliable majorities.
"This election will determine if the government can succeed in differentiating Colombia from the leftist trends in the region, by siding with Chile and Mexico instead of siding with Venezuela and Argentina," Mr. Echeverry said.
Colombia remains a major ally for the United States in a region where left-wing policies and anti-American sentiment have won favor in recent elections.
About 26.5 million Colombians are registered to vote in the election for the 268-member Congress, which is made up of 102 senators and 166 members of the lower house.
Mr. Uribe wants Congress to help him shift the tax burden from companies to consumers in an effort to increase investment.
The free trade pact, signed last month, is seen by economists as important for Colombia's future competitiveness, and Wall Street is clamoring for changes in tax law needed to attract foreign investment to the violence-scarred country.
Dozens of people, most of them civilians, have been killed in recent weeks by the Revolutionary Armed Forces of Colombia, the rebel group that traditionally steps up attacks at election time. Thousands of people die and tens of thousands are forced from their homes every year in Colombia's decades-old guerrilla war.
A car bomb exploded Sunday in the western jungle province of Chocσ, but no one was wounded, the army said. No incidents were reported at the country's polling places, the police said.
"Things are calm," a voter in Bogotα said after casting her ballot. Most of us are voting today just as we always have."
