95% — Will Democrats win the 2026 national House popular vote by at least 6 percentage points Leader: Democrats, ≥2% at 95% · Kalshi 95% · 8 contracts · $0 volume · medium confidence Updated 2026-09-25 07:16:58 UTC Tracks the leading outcome in a winner-take-all prediction market set with 8 outcomes. Why this matters: This probability reflects the likelihood that Democrats will capture more than half of votes cast in the 2026 House elections by a margin exceeding 6 percentage points. The 86% price on the narrower ≥2 point threshold suggests traders view a Democratic popular vote advantage as highly probable, but the sharp decline to 27% on the ≥10 point threshold indicates substantial uncertainty about margin size. Current conditions favoring Democrats—such as historical anti-incumbent patterns and potential dissatisfaction with Republican governance—would need to persist through November 2026 to reach a 6-point margin. Conversely, economic improvement, shifts in voter turnout dynamics, or changes in congressional redistricting effects could narrow Democratic advantages. The election on November 3, 2026, will definitively resolve this question by determining the actual national House popular vote margin. Key factors: - Historical anti-incumbent sentiment typically benefits the opposition party in midterm-equivalent cycles; current economic and approval conditions suggest Democratic tailwinds persist - The gap between ≥2% (86¢) and ≥6% (implied lower) prices indicates traders assign meaningful probability to smaller Democratic margins (2-6 points), constraining the likelihood of larger victories - Turnout composition and swing-district performance remain uncertain; suburban and youth voting patterns will meaningfully influence final margin - Redistricting effects from 2020 Census favor Republicans structurally; Democrats must overcome inherent House map disadvantages to achieve 6+ point popular vote margins - Election scheduled for November 3, 2026, serves as single point of resolution; no interim data releases or events will update popular vote estimates until voting concludes Contracts: - Will Democrats win the 2026 national House popular vote by at least 2 percentage points?: Democrats, ≥2% — 95¢ Kalshi $0 (weight 13%) - Will Democrats win the 2026 national House popular vote by at least 4 percentage points?: Democrats, ≥4% — 91¢ Kalshi $0 (weight 13%) - Will Democrats win the 2026 national House popular vote by at least 6 percentage points?: Democrats, ≥6% — 87¢ Kalshi $0 (weight 13%) - Will Democrats win the 2026 national House popular vote by at least 8 percentage points?: Democrats, ≥8% — 73¢ Kalshi $0 (weight 13%) - Will Democrats win the 2026 national House popular vote by at least 10 percentage points?: Democrats, ≥10% — 46¢ Kalshi $0 (weight 13%) - Will Democrats win the 2026 national House popular vote by at least 12 percentage points?: Democrats, ≥12% — 22¢ Kalshi $0 (weight 13%) - Will Democrats win the 2026 national House popular vote by at least 14 percentage points?: Democrats, ≥14% — 5¢ Kalshi $0 (weight 13%) - Will Democrats win the 2026 national House popular vote by at least 16 percentage points?: Democrats, ≥16% — 3¢ Kalshi $0 (weight 13%) --- ## 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: 2026-09-25T06:20:49.176Z* By SimpleFunctions — https://simplefunctions.dev/ Cite as: "95% per prediction markets (SimpleFunctions, September 2026)" Canonical: https://simplefunctions.dev/answer/housepopvotemargind Full data: https://simplefunctions.dev/api/public/query?q=Will%20Democrats%20win%20the%202026%20national%20House%20popular%20vote%20by%20at%20least%206%20percentage%20points Provider: SimpleFunctions — https://simplefunctions.dev