Updated

Colombia's former leftist guerrillas face their first electoral test as a political party Sunday in congressional voting also seen as a measure of the strength of the country's factions two months before presidential elections.

Analysts see the balloting for the Senate and House of Representatives as a test of the democratic viability of the FARC, whose fighters laid down their arms following a historic peace pact last year and converted into a political movement. The Revolutionary Armed Forces of Colombia gave their new party the same FARC initials as the rebel group.

Casting a shadow over the FARC's political ambitions is the recent decision to withdraw its candidate from the presidential race for health reasons. Ex-rebel leader Rodrigo Londono underwent successful hearth surgery last week and earlier suffered a stroke.