The election was set to be the calmest in half a century of conflict in Colombia, with the former rebel movement FARC spurning jungle warfare for politics, and the ELN - the country's last active rebel group - observing a cease-fire.
"This is the first election in half a century when we will vote in peace, without the FARC as an armed group, but as a political party," said President Juan Manuel Santos, who signed a peace deal with the Revolutionary Armed Forces of Colombia (FARC) in November 2016.
The peace accord with FARC guarantees their new political party 10 of the 280 seats in the new Congress. The party uses the same Spanish acronym, which now stands for the Common Alternative Revolutionary Force, and replaced its crossed-rifles insignia with a red rose.
But opinion polls give it little chance of adding to its 10 free seats, following a disastrous campaign during which its rebels-turned-politicians were largely drowned out by a tide of public revulsion over crimes committed during the conflict.
Candidates were mobbed by angry crowds at rallies and the party canceled public meetings.
The fledgling party suffered a fresh blow days before the election when its leader, Rodrigo "Timochenko" Londono, pulled out of the presidential race after heart surgery.