40% — Will the margin of victory for Flávio Bolsonaro in the first round of the 2026 Brazilian presidential election be between 5% and 10% Leader: Lula da Silva, 0-5% at 40% · Kalshi 40% · 5 contracts · $111 volume · medium confidence Updated 2026-09-21 23:35:02 UTC Tracks the leading outcome in a winner-take-all prediction market set with 5 outcomes. Why this matters: This contract resolves if Flávio Bolsonaro wins Brazil's first-round presidential election with a margin between 5% and 10% over the second-place finisher. Currently priced at 10 cents, it reflects relatively low probability compared to stronger outcomes favoring Lula da Silva. Market pricing suggests traders view a Bolsonaro victory with this specific margin as unlikely, with heavier weight on either Lula winning by a larger margin (47 cents for Lula ≥15%) or Bolsonaro performing worse if he wins at all (4 cents for Bolsonaro 0-5%). The outcome depends on voter turnout patterns, regional voting coalitions, and whether either candidate consolidates support more effectively than opponents. The first-round vote is scheduled for October 2026, and pre-election polling trends through September will be the primary driver of repricing before resolution. Key factors: - Current polling spreads between Lula and Bolsonaro and whether the gap narrows or widens between now and October 2026 - Regional voting patterns in Northeast and Southeast Brazil, which historically determine margin magnitudes - Voter turnout rates and turnout differential by demographic group, affecting both absolute votes and margin calculations - Third-candidate performance and whether any challenger consolidates enough support to compress the top-two margin - Late campaign events or economic data (inflation, unemployment, exchange rate moves) released in final months that could shift voter preference intensity Contracts: - Will the margin of victory for Lula da Silva in the first round of the 2026 Brazilian presidential election be between 0% and 5%?: Lula da Silva, 0-5% — 40¢ Kalshi $7 (weight 6%) - Will the margin of victory for Flávio Bolsonaro in the first round of the 2026 Brazilian presidential election be between 0% and 5%?: Flávio Bolsonaro, 0-5% — 27¢ Kalshi $27 (weight 25%) - Will the margin of victory for Lula da Silva in the first round of the 2026 Brazilian presidential election be between 5% and 10%?: Lula da Silva, 5-10% — 9¢ Kalshi $0 (weight 0%) - Will the margin of victory for Flávio Bolsonaro in the first round of the 2026 Brazilian presidential election be between 5% and 10%?: Flávio Bolsonaro, 5-10% — 3¢ Kalshi $77 (weight 69%) - Will the margin of victory for Lula da Silva in the first round of the 2026 Brazilian presidential election be above 15%?: Lula da Silva, ≥15% — 3¢ Kalshi $0 (weight 0%) --- ## Methodology SimpleFunctions aggregates live YES-side prices from Kalshi and Polymarket contracts bound to this question. For binary topics the headline is the liquidity-weighted mid-price (weight = log(1 + 24h volume) × freshness, where freshness is 1.0 if updated <24h, 0.7 if <7d, 0.4 otherwise). For multi-outcome (winner-take-all) topics the headline is the current leader's price — disjoint outcomes are never arithmetically averaged. Snapshots refresh every 5 minutes during market hours. ## SF Signal - SF Index, regime, and 30d Brier calibration are computed separately and surfaced at https://simplefunctions.dev/admin/calibration. - No SimpleFunctions index / regime / calibration signal is bound to this topic yet — the headline above is market-derived only. --- *Last verified: 2026-09-21T23:21:00.677Z* By SimpleFunctions — https://simplefunctions.dev/ Cite as: "40% per prediction markets (SimpleFunctions, September 2026)" Canonical: https://simplefunctions.dev/answer/brpres1mov Full data: https://simplefunctions.dev/api/public/query?q=Will%20the%20margin%20of%20victory%20for%20Fl%C3%A1vio%20Bolsonaro%20in%20the%20first%20round%20of%20the%202026%20Brazilian%20presidential%20election%20be%20between%205%25%20and%2010%25 Provider: SimpleFunctions — https://simplefunctions.dev