PLAYGROUND · MP-26 v0.5

Play with the forecast

Three tools to test the forecast live: move the national environment and watch both chambers react, paint your own map, or cross any two variables across every county and district.

Races you can move: 470
Simulations per scenario: 50,000
Counties in the data lab: 3,100+

YOUR SCENARIO

Move the map

National

National swing

Generic-ballot movement; each race absorbs 70%, as in the model.

Polling error

A systematic miss: every race moves by the full amount.

Regional swing

Rust Belt

Sun Belt & South

Middle & Rural

West Coast & Pacific

Mountain West

East Coast

Demographic swing

Hispanic voters

Black voters

White non-college

College graduates

How this works

Every one of the 470 races starts from its published MP-26 v0.5 margin. Your sliders add to it, linearly:

margin = model + national × 0.7 + polling error + region + Σ (group swing × group share)

A group's share is its share of the district's population (the state's, for Senate races) in the Census ACS 2024 5-year profiles. A 10-point Hispanic swing therefore moves a 50% Hispanic district by 5 points and a 5% one by half a point. White non-college is estimated as white share × (1 − bachelor's share). Population shares are not electorate shares, so treat group swings as rough.

Both chambers are then re-simulated in your browser with the model's own engine: a shared national error plus local error for every race. While you drag, 6,000 quick runs; once you stop, the full 50,000.

Simulating…

HOUSE

218 for majority

99%Democratic majority

1%Republican majority

D 245 · 190 RSimulating…

Same as the published forecast

150218 seats320

SENATE

51 for majority

77%Democratic majority

23%Republican majority

D 53 · 47 RSimulating…

Same as the published forecast

3851 seats64

50–50 goes to Republicans: the Vice President breaks ties.

435 DISTRICTS · YOUR SCENARIO

239 districts lean Democratic

RDFlips

Hover a district to compare; click to open its race.

Senate tiles: the 35 seats on the ballot. Grey tiles have no race in 2026.

VS THE PUBLISHED FORECAST

No race changes favourite

Move a slider or pick a preset: races whose expected winner changes appear here.