**Final pre-election surveys from Datafolha, Quaest, CNT/MDA, and AtlasIntel showed the two leading candidates—incumbent Luiz Inácio Lula da Silva and Senator Flávio Bolsonaro—receiving roughly 42-48% of valid votes each, with the remainder split among minor contenders in the low single digits.** Brazilian rules require more than 50% of valid ballots for an outright first-round victory on October 4, triggering an automatic runoff on October 25 if unmet. The persistent shortfall below that threshold across multiple pollsters, alongside a fragmented field and historical patterns of Brazilian presidential contests requiring second rounds, drives the near-certain trader consensus reflected in the 99.2% implied probability for “No.” Late shifts in turnout, regional mobilization, or polling errors could theoretically alter the outcome, though available evidence indicates limited scope for such movement.