The close first-round results on October 4, with Allyson Bezerra (União) edging Cadu de Lula (PT) by just 0.78 percentage points, have set up a tight runoff on October 25 that drives the market's emphasis on narrow margins or an upset. A Quaest poll conducted October 9–12 showed the candidates in a technical tie at 45% to 42% among likely voters, reflecting limited movement from third-place finisher Álvaro Dias (PL) and the influence of undecided or shifting voters. Regional municipal vote splits, party coalition dynamics in the Northeast, and the short campaign window to consolidate support keep probabilities concentrated on low-single-digit or sub-6% victories for either side, consistent with trader pricing that assigns substantial weight to "other" outcomes amid the inherent volatility of Brazilian state runoffs.