Explaining and Predicting the Two-Party Mid-Term House Vote Share: 2026 Prediction

Abstract

History of Voting EquationsI first estimated an equation explaining the two-party vote share for president in 1978-Fair (1978)).The general theory behind the equation is that a voter evaluates the past economic performances of the competing parties and votes for the party that provides the highest expected future utility.Within the context of the theory, one can test both how far back voters look in evaluating the economic performances of the parties and what economic variables they use in their evaluations.Many tests were performed in Fair (1978) using data on U.S. presidential elections beginning in 1916.The results supported the view that voters look only at the economic performance of the current party in power, not also, for example, the performance of the opposition party the last time it was in power.The growth rate of per capita real GDP and the inflation rate were the two economic variables.The theory allows some voters to always vote for only one party.It requires only that there are some "swing" voters who are influenced by the economy.