Pedro Pablo Kuczynski, a veteran economist and politician, and Keiko Fujimori, daughter of the controversial former Peruvian President Alberto Fujimori, were neck and neck after the second round of presidential voting on Sunday.
Mariano Cucho, head of Peru's national election office, ONPE, said officials are awaiting ballots cast in the inner provinces and absentee ballots cast abroad. Peruvians in other countries represent around 3% of those entitled to vote.
With more than 92% of the vote counted Monday, the center-right Kuczynski was leading 50.3%
to Fujimori's 49.6%, according to election officials
Kuczynski was ahead by more than 103,000 votes.
A controversial past
Fujimori's face is familiar to Peruvian voters.
She was appointed to act as first lady for part of her father's presidency after her parents divorced, and she was elected to Peru's Congress in 2006.
As president from 1990 to 2000, he is credited with restoring economic stability to the country and defeating the Maoist Shining Path guerrillas, who carried out terrorist attacks. But he had an authoritarian streak that led to accusations of human rights abuses and corruption.
In separate trials, Fujimori was found guilty of breaking into the home of a former spy chief to steal incriminating videos, taking money from the government treasury to pay the spy chief, authorizing illegal wiretaps and bribing lawmakers and journalists.
In 2009, he was sentenced to 25 years in prison after being convicted of authorizing the operation of a death squad responsible for killing civilians.
Some worry that Keiko Fujimori would pardon her 77-year-old father and take a similar approach to the presidency if she wins.
The 41-year-old candidate has rejected the accusations, saying they're lies fueled by her political enemies.
In a 2008 interview, she said she wouldn't hesitate to grant her father amnesty because she believes he is innocent. She later backed away from those remarks.
PPK's notable career
Kuczynski, who has a long career in business and politics, has stressed the point that "the record we have is that we are clean."
He is a former World Bank executive and ex-prime minister of Peru who has also served as finance and energy ministers.
Despite having a long career as a public official, Kuczynski got a taste of running for elected office in his 70s, when he was a presidential candidate for the first time in 2011.
Known as PPK, he's the son of a German man and a French woman, who's married to an American and whose children live in the United States.
He did not renounce his U.S. nationality in 2011 as his adversaries demanded. In that election he came in third.
Close to turning 78 years, and now having renounced his U.S. nationalilty, PPK has said that presidency of Peru will be his last job.
"Age is a very good thing if you have a good head and experience, and this we have in abundance," he said.
The winner will lead Peru for the next five years.
Controversies and protests have marred the campaign.
Demonstrators on both sides have clashed in the last few weeks, but there were no reports of violence during Sunday's voting.
Keiko Fujimori took to Twitter after polls had closed to say that she was "optimistic" and thanked the country for its support.
Kuczynski said that he was grateful to political and civil groups, and citizens' commitment to democracy.