Background Information on the ‘Bread, Incumbency and Balance’ Model for the US House of Representatives

According to the ‘Bread, Incumbency and Balance’ model, the number of seats won by the president’s party in postwar elections for the US House of Representatives is well explained by three fundamental determinants:

(1) Positively by weighted-average growth of per capita real disposable personal income over the two-year (8 quarter) Congressional term.

(2) Positively, up to a stability limit, by the number of House seats won by the president’s party at the previous House election, which reflects incumbency advantage.

(3) Negatively by the vote margin of the incumbent President at the previous election – a factor that only affects mid-term congressional elections and reflects the electorate’s desire for partisan “balance” in control of national government. The desire for balance operates interactively by reducing the effect of incumbency: The bigger a sitting president’s vote margin in the previous on-year election, the weaker is the incumbency effect on House seats going to the president’s party at each midterm election.

My research indicates that no other objectively measured, pre-determined or exogenous variable systematically affected postwar partisan divisions of seats in the House of Representatives. As in presidential voting, other factors of course influence House election results, however, they are transitory rather than persistent, varying randomly from election to election, thus defying ex-ante objective measurement.

To learn about the theoretical framework and technical mechanics of my Bread, Incumbency and Balance’ model of voting outcomes in the US House of Representatives, you may consult the following: