Updating the Fundamentals: Forecasting the 2026 Midterm Election Post-Gallup

Abstract

Statistical forecasts of congressional and presidential elections have become a regular feature of our discipline, and most rely on presidential approval, which has historically been provided by the polling firm Gallup.In 2025, Gallup discontinued its monthly presidential approval series, ending 88 years of continuous approval data collection.We introduce a proxy measure derived from RealClearPolitics approval estimates (Adj.R 2 = 0.97).Updating the Lewis-Beck and Rice political economy model of seat change, and applying it to the 2026 midterm elections, the model anticipates a Republican loss of roughly 42 House seats and 9 Senate seats.Finally, we present a quarterly forecast series for the House and Senate from 1948 to the present and show how early in the cycle these forecasts acquire predictive value.