Peru's presidential election results have been thrown into uncertainty after tens of thousands of voters were denied ballots on election day, forcing authorities to grant an exceptional voting extension into Monday — the first time in the country's history that a presidential election has stretched across two days.

The disruption began early Sunday morning in Lima, the capital, when long queues formed outside polling stations that never received their ballot papers. A private contractor hired by Peru's national electoral authority, known by its Spanish acronym ONPE, had simply failed to deliver the materials. More than 52,000 eligible voters in Lima were left unable to cast their ballots. Police anti-corruption units later raided ONPE's offices, and an investigation into the contracting firm was opened. After hours of uncertainty over whether the entire election might need to be rerun, Peru's supreme electoral court ruled that the 13 affected polling stations would remain open on Monday afternoon to allow the missing votes to be cast.

The chaotic backdrop did not prevent a partial count from emerging. With roughly 45 percent of votes tallied by early Monday morning, right-wing candidate Keiko Fujimori — the daughter of former authoritarian president Alberto Fujimori, who ruled Peru in the 1990s and was later imprisoned for human rights abuses — held a narrow lead with approximately 17 percent of the vote. Former Lima mayor Rafael López Aliaga, also on the right, trailed closely at 15.6 percent, while liberal former culture minister Jorge Nieto stood at 13.4 percent, still within reach of a place in the second-round runoff scheduled for 7 June.

The delay has raised concerns about the integrity of Monday's supplementary vote, given that partial results were already publicly available when those voters went to cast their ballots. López Aliaga, who had been slipping in pre-election polls, alleged fraud as early as Sunday morning on social media platform X, and by Sunday evening had called his supporters into the streets. Hundreds of his backers gathered outside the supreme electoral court, where police in riot gear were deployed. The head of the European Union's electoral observation mission, Annalisa Corrado, pushed back against those claims, stating that the EU's 150 deployed observers had found no evidence of deliberate manipulation — only logistical delays.

Why this matters: While 52,000 missing votes may seem minor against an electorate of 27 million, recent history shows their potential weight. In Peru's last presidential election in 2021, leftist Pedro Castillo defeated Keiko Fujimori in the runoff by just 44,000 votes. With the race this time again appearing razor-thin, every ballot — and every allegation of irregularity — carries significant political consequence in a country that has seen seven presidents in the past decade.