The right-wing daughter of a jailed former president faces a left-wing former army commander in a presidential run-off that has polarised Peru.
Seeking to return to the presidential palace she called home as a child, Keiko Fujimori has portrayed herself as a champion of business.
Her father, Alberto, is serving 25 years for corruption and the use of death squads.
Ollanta Humala, in contrast, reached the second round by courting rural Peruvians, who feel ignored by elites in the capital, Lima.
Both have tried to appeal to undecided voters, who may prove crucial. Fujimori has apologised for her father’s excesses while Humala has promised to manage the economy prudently.