An Inquiry of Bellwether Counties in US Presidential Elections

Abstract

Bellwethers have been studied for decades in the realm of election forecasting. Presidential election forecasting has historically focused on the study of bellwethers at the level of the state, likely due to the fact that presidential candidates win electoral college votes based upon the winner of the popular vote in each state. However, states can be difficult to study due to their large sizes and diverse political environments, leading these authors to examine whether bellwethers can also be studied at the finer resolution of individual counties. To do so, the popular vote winner of each county for every presidential election from 1980 through 2016 was tabulated and mapped, yielding 19 true bellwether counties for the period. These counties were geographically clustered in the Midwest and in the Northeast. Demographically, the bellwether counties tended to be whiter, older, less educated, have lower median incomes, have a lower percentage of workers in the labor force, and have higher rates of vacant housing than the country as a whole. Finally, numerical bellwether scores for all 3142 counties in the US were computed based upon the number of elections in which each county voted for the winner of the election. Counties with the highest bellwether scores were also disproportionately found in the Midwest and in the Northeast.