The tight first-round contest on October 25, where incumbent Iliana Iotova secured 34.76% to Andrey Gyurov’s 31.95% amid record-low 23% turnout, has produced substantial uncertainty around the November 1 runoff margin. Traders assign the highest probability to “Other” because voter mobilization from eliminated candidates, including nationalist Kostadin Kostadinov’s 12.55% share, remains unpredictable and could shift outcomes in either direction. Iotova benefits from endorsements by the ruling Progressive Bulgaria party and Prime Minister Rumen Radev, while Gyurov draws support from pro-Western opposition groups, with the candidates differing on foreign policy toward Russia and Ukraine. Historical patterns of low-turnout second rounds and the absence of a first-round debate further complicate precise margin forecasts, keeping probabilities distributed across narrow victory bands rather than decisive leads.