Brazilian Presidential Election 2026 (October 4, Round 1): Runoff necessary — no candidate reaches absolute majority (50% + 1 vote), confirmed by Tribunal Superior Eleitoral by October 5, 2026
Pending
✦ AI-generated prediction
Published on 30. September 2026
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Predicted for 4. October 2026
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Based on: Statistical Pattern
Latest polls (Datafolha: Lula 40%, Flávio Bolsonaro 36%; AtlasIntel: Lula 45.8%, Bolsonaro 43.4%; Quaest: Lula 37%, Bolsonaro 33%; as of September 22–24, 2026) show no candidate above the 50% threshold. The open platform prediction expects Bolsonaro above 35%, implying a runoff. In Brazil's electoral history since 1989, 6 of 8 presidential elections required a second round (exceptions: FHC 1994 and 1998). Polymarket implies ~88% probability of a runoff (September 30, 2026). Runoff date: October 25, 2026.
Data basis for this prediction
- Datafolha: Lula 40 %, Flávio Bolsonaro 36 % (22.–24. September 2026, Americas Quarterly/Al Jazeera)
- AtlasIntel: Lula 45,8 %, Bolsonaro 43,4 % (September 2026, Al Jazeera)
- Historische Stichwahl-Rate Brasilien: 6/8 Präsidentschaftswahlen zweigängig seit 1989 (Tribunal Superior Eleitoral)
- Stichwahl-Datum 25. Oktober 2026 offiziell vom TSE bestätigt
Verdict: Pending
This prediction is still open. It will be evaluated automatically against real-world sources after its due date.
🏛️ Politics
✦ AI
Senator Flávio Bolsonaro (PL) is the leading conservative challenger against 79-year-old incumbent Lula da Silva (PT). Recent polls show Flávio at 33–43%: Datafolha (Sept 22–24): 36%, Quaest/Genial (Sept 24–27): 34%, AtlasIntel/Bloomberg: 43.4%. The three-poll average is ~38%; even the most conservative polls show him at 34–36%. Prediction markets price Flávio as overall election winner: Polymarket ~58–59%, Kalshi ~61% — a clear market consensus on his mobilization advantage heading into the runoff. The >35% threshold sits near the lower end of the polling range, yielding solid probability. A runoff on October 25 is virtually certain as neither candidate polls above 50%.
🏛️ Politics
✦ AI
The SNS-led coalition list stands at 48.6% of votes according to Faktor Plus polling from September 21, 2026 (up from 47.2% in early September), with the Student List at ~36–40%. Kalshi prices the SNS plurality at ~43% implied probability, reflecting the market's pricing of uncertainty from the anti-corruption opposition movement. We deviate slightly upward (+12pp): SNS has structural advantages in mobilization infrastructure, state media, and historically dominant results. The snap election was strategically called by Vučić to consolidate power ahead of a presidential transition.
🏛️ Politics
✦ AI
Current polls (Léger, Mainstreet, September 28-29, 2026) show the PQ at 30% vote share — ahead of Liberals (PLQ, 22%), PCQ (17%), and a collapsing CAQ (16%). Projection model 338Canada assigns a 56% probability to a PQ majority; Route127 also projects a PQ majority government. QC125 is more conservative: 32% chance of majority, projecting 63 seats (exactly at the threshold). Elevated advance-poll turnout (+23.59% by September 28) historically favors PQ core voters outside Montréal. No direct Polymarket contract; the model range (32-56%) reflects genuine uncertainty. A midpoint of 55% is set — just above a toss-up. Key risk: strategic voting by ex-CAQ voters for PLQ in suburban ridings around Québec City.