Monte Carlo · 100,000 runs · Polymarket + Kalshi probabilities
Running simulations…
Fetching Polymarket + Kalshi prices, then running 100,000 scenarios
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We run the election 100,000 times using betting-market prices as each race's baseline odds. Races don't miss independently: every simulated election draws a shared national swing, a swing per region, and one per state (fat-tailed, so 2016-style systemic misses happen occasionally), then decides each race around its shifted margin. Each bar shows how often Democrats finished with exactly that many seats; bars past the majority line mean Democratic control.
| State | Current | D win % | Morris-style model | Mkt margin | Poll avg | '24 Pres | Cook PVI | Fundraising (CoH) | Pivotal | Probability bar | Source |
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Same idea as the Senate chart: 100,000 simulated elections, each bar the share of simulations landing on that exact seat count. All 435 districts are simulated — districts without a betting market carry their 2024 margin as a cushion and can still flip when a simulated wave breaches it.
All 435 districts simulate: — at market prices; the other — carry their 2024 margin as a cushion and can flip when a simulated wave breaches it.
| District | D win % | Morris-style model | Mkt margin | Poll avg | '24 Pres | Cook PVI | Fundraising (CoH) | Pivotal | Probability bar | Source |
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Instead of asking "who wins each race?", these markets ask "exactly how many seats?" — traders buy brackets like "Democrats win 51 seats." That prices an entire probability distribution directly. Bars are the markets' own views; the white dashed line is our simulation, whose correlated-swing sizes are calibrated so its House-majority odds match the control markets (it runs narrower than the bracket ladders — the markets disagree internally about how much uncertainty there is). The green dashed line swaps in G. Elliott Morris's published polling-error magnitudes, including a "things can still change" term that grows with time left before the election — it runs wider than the market lines because market prices already discount future news.
A gerrymander wins extra seats by spreading a party's voters efficiently — many districts won by deliberately thin margins. The catch: if the political wind shifts, all those thin seats flip together. That's a "dummymander." The chart counts, across 100,000 simulations, how many engineered seats the drawing party loses; the table lists each engineered seat and its market-implied chance of backfiring.
| Seat | Drawn by | Map | Mkt margin | Poll avg | '24 Pres | P(backfire) |
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Each dot is one competitive district. Left-right = how the district usually leans (its fundamentals); up-down = the market's or the model's win probability right now. The dashed line is the fitted logit curve — the normal S-shaped relationship between lean and win odds; a dot far above or below it is a race behaving unusually for its turf — a strong candidate, a scandal, or a redrawn map. Click any dot to open its details — and selecting a race in the tables above highlights its dot in all the scatter plots.
Each dot is one race: across = what the leading Republican has raised this cycle, up = what the leading Democrat has (we take each party's top fundraiser among candidates actually filed for the 2025–26 cycle, so retirees' leftover war chests don't count). The dashed 45° diagonal is equal funding — a dot above it means the Democrat is out-raising. Color shows who the markets expect to win: solid red means the Democrat has a 20% chance or less, solid blue 80% or more, and the shades in between are the genuinely contested races. A red dot far above the line is a race where Democratic money isn't buying market confidence — and vice versa. Click any dot to open the race's details; selecting a race in the tables highlights its dot here.
Pick any two metrics and see how the races line up. Dots are colored by market win odds and labeled by race; click any dot to open that race's details, and selecting a race in the tables highlights its dot here. Money axes use log scales. When the Y axis is a probability, a fitted logit curve is drawn, and when an axis is market or model win probability a yellow line marks each chamber's marginal seat under that ordering — the one on the margin of majority (the time machine re-ranks each day, so the line jumps to whichever seat is marginal on the day shown). '24 presidential margins use The Downballot's 2026-lines calculations; redrawn districts are omitted only from PVI and last-result axes (still old-lines data).
Everything above is a snapshot of right now. This section records one snapshot per day so you can see the story move: control odds drifting, projected seats creeping, and which races are tightening. Gaps in a line mean no snapshot was recorded that day.
Each ridge below is one week's seat distribution (the newest ridge is today's) — like stacking each week's chart behind the next. Ridges getting taller and narrower over time = growing confidence about the outcome. The first pair comes from our simulations, the second directly from the market's seat-count brackets.
Every fresh poll is news — this table asks whether the news mattered. For each recent poll we compare the race's D-win probability just before the poll landed to where it stood 24 and 48 hours later, in both the market price and the fundamentals + polls model. Impact is measured from daily snapshots, so a dash means the window isn't covered yet (snapshots build forward from the first recorded day). A move isn't proof the poll caused it — other news moves prices too — but big jumps right after a surprising poll are usually no coincidence.
| Race | Pollster | Asked | Released | D | R | Margin | Rating | Weight | Mkt D win | Market impact (24h / 48h) | Model impact (24h / 48h) |
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The "Morris-style model" is a fundamentals-plus-polling regression: our independent approximation of the fundamentals methodology G. Elliott Morris published for 538's 2024 congressional forecasts — partisan lean, past results, incumbency, individual-contribution share, and expert ratings, here fit to market prices with polls added — and the green seat-distribution overlay uses his published polling-error magnitudes. It is a simplification, not his model, and is not affiliated with or endorsed by him or 538. Sources: Morris, G. Elliott, "How 538's 2024 House election forecast works" and "How 538's 2024 Senate election forecast works," 538 / ABC News, October 2024.
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