Peru will hold its presidential election runoff on Sunday between right-wing Keiko Fujimori and left-wing Roberto Sánchez Palomino.

The election remains open-ended, as voter intention is locked in a technical draw. Those who have not yet made a decision will be key to define who will be Peru’s next president.

According to a private poll issued by consultant agency Ipsos, Sánchez leads slightly with 43.8% support over Fujimori’s 43.2%. Thirteen percent of voters remain undecided. The poll was only sent to Ipsos clients, as electoral surveys cannot be published in the week leading up to elections in Peru.

While the odds seemed to be on Fujimori’s side when the results were announced after an unprecedented delay of over a month in the vote count, this may not necessarily be the case on Sunday.

Fujimori won the first round with 17.2% of the vote, while Sánchez Palomino clinched second place with 12% after a weeks-long, neck-and-neck dispute with far-right Rafael López Aliaga (11.9%), who denounced there had been electoral fraud.