The conventional read of Peru's presidential runoff is that Keiko Fujimori's accumulation of endorsements — from Rafael López Aliaga's Renovación Popular 1425, Avanza País 14, and the PPC 14 — has positioned her as the near-certain victor. Multiple outlets report Fujimori leading Roberto Sánchez in most polls 6182429, and her campaign has locked in higher voter loyalty: according to El Comercio, citing Datum Internacional, 65% of decided voters say they will not change their minds 18. The narrative writes itself: a disciplined right-wing bloc coalescing against a scattered leftist alternative.
“The undecided bloc outnumbers the margin separating the candidates, and geographic fractures — Lima versus the south — ensure the winner inherits not a mandate but a veto.”
The trouble is the electorate refuses to coalesce. As reported by Infobae 24, 13.4% of voters remain undecided, and 22.6% intend to vote blank or spoil their ballot. La República reports, citing IEP, that the undecided share has doubled to 26% 18. These are not passive abstainers — they are active rejectionists, and they outnumber the margin separating the candidates. In the most recent Ipsos simulation cited by Peru21 29, Fujimori leads Sánchez 51.4% to 48.6% among valid votes — a gap of 2.8 points. But that rests on the assumption that blank and invalid votes distribute evenly. They will not.
The geographic split underscores the fragility. According to El Comercio 618, Fujimori dominates Lima Metropolitana with 51%, while Sánchez leads the centre (35% vs. Fujimori's 30%) and the south (38% vs. 28%). El Comercio reports Sánchez won over 86% of votes in Puno 28, a result reflecting not ideological fervour but state abandonment: voters in the south see no material dividend from the economic model Fujimori's backers champion. The coalition she has assembled is Lima-centric and economically liberal — precisely the profile that failed her in 2021.
What distinguishes 2026 from that contest is not Fujimori's strength but Sánchez's vulnerability. Infobae reports he faces accusations of corruption and misuse of party funds, denied by the Ministerio Público 25, and his association with Antauro Humala — convicted for the Andahuaylazo uprising 2527 — has cost him centrist credibility. Yet the undecided bloc is not shifting to Fujimori. El Comercio, citing Datum, reports 57% of voters consider the upcoming debate decisive 21, which suggests they are waiting for a reason to commit, not preparing to endorse the frontrunner.
The real variable is institutional mistrust. Infobae reports that Ipsos president Alfredo Torres prematurely declared Fujimori the winner based on internal calculations 3, prompting the electoral tribunal to order an audit 3. Rafael López Aliaga is reported by Infobae to have claimed ONPE and JNE officials will "share a cell" with Torres 16 — a conspiracy theory that Peru Check denied, noting the 900k ballot series has been used in prior elections 16. Fujimori herself is reported by Al Jazeera and El Tiempo to have claimed election fraud 726, a move that may consolidate her base but repels the undecided middle.
The winner will govern a polarised legislature under a new bicameral system 14, facing a Congress elected under proportional representation and a public that, according to El Mundo, approves of the current government at just 18.7% 30. Whoever prevails on 7 June 26814252630 will inherit not a mandate but a veto: the south against Lima, the blank-voters against both camps, and a fragmented legislature against executive ambition. Coalition arithmetic cannot bridge a chasm this wide.