Congressional Electoral Risk Workbench Based on The Economist (@TheEconomist)

House Republican Hold Probability & Tail-Risk Calculator

A 1-point polling miss in isolated districts rarely flips a national legislative majority. But when correlated non-response errors, late deciders, and structural incumbency compound simultaneously, why are Republican chances of retaining the House closer to 10% than 1%?

Modeled GOP Hold Probability
10.4%
Plausibility of keeping ≥ 218 seats
Survival Verdict
Plausible Tail-Risk
Classification vs 1% naive baseline
Tail-Risk Multiplier
3.8x
Elevated odds vs Gaussian baseline (2.7%)
Tipping-Point Seats Needed
218
Majority threshold in 435-seat chamber

Projected Republican Seat Distribution

1% Naive Gaussian Model Modeled Tail Risk (10.4%) 218 Majority Line
Methodology Note: Standard uncalibrated models assume independent polling errors across 435 races, yielding an artificial <1% probability of GOP control. When a common correlated national error factor is introduced (as observed in historical cycles), the probability density shifts outward toward 10.4%, preserving a viable survival tail.

Key Tipping-Point Battlegrounds & Resilience Index

Showing 8 Critical Defending Seats (Sorted by Closeness)

Races where the structural incumbency moat and late-breaking swing have the largest probability multiplier of shifting the district beyond the Democratic flip threshold:

District & Incumbent State Cook PVI Polling Baseline Modeled Margin Flip Vulnerability Projected Status
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