Two researchers, Yusaku Horiuchi, Woo Chang Kang, have done a very interesting study examining the effects of rain on US voter turnout and voter preference. The study, “Why Should the Republicans Pray for Rain? Electoral Consequences of Rainfall Revisited”, recently was published in the journal, American Politics Research, and was conducted by Dartmouth College, an Ivy League university in New Hampshire,  and the Australian National University in Canberra, the capital of Australia. Take a look at the abstract:

Existing studies—most importantly, Gomez, Hansford, and Krause—provide empirical support for an idea often embraced by popular media: The vote share of the Republican Party (as the percentage of total votes) increases when it rains, because the magnitude of decrease in turnout is larger among Democratic vis-à-vis Republican supporters.

Considering the compositional nature of aggregated data, we show that the alleged Republican advantage derives in part from an increase in the number of votes for the Republican Party. Based on the extensive literature of psychology and related fields, we provide a possible interpretation of this counter-intuitive empirical finding. Methodologically, our evidence suggests that researchers must be alert when using rainfall as an instrument to estimate the causal effects of voter turnout on electoral outcome.

According to a write up on the study by Science Daily, co-author Yusaku Horiuchi said their work “suggests that weather conditions may affect people’s decisions on not only whether to vote but also who they vote for.” Also from that article:

The findings revealed that at least 1 percent of voting age adults in the U.S. who would have voted for a Democrat had the weather been good, voted instead for a Republican on rainy election days. The change in party preference may be attributed to a psychological behavior, where voters may be more averse to risk during poor weather conditions. Earlier studies have identified a correlation between ideological and political orientations in which conservatives or Republicans tend to be more averse to risk than liberals or Democrats.

As covered on Democracy Chronicles, other unexpected factors that research suggests affect US voter turnout now include boredom, delayed onset adulthood, cigarette smoking, wind speed, bad weather forecasts and, as suggested today, just the rain. This type of research is highlighted in our Election Science archives as well as other important research in political science as it relates to democracy, the ultimate invention in political science. Be sure to also check out our Election Technology section and our articles on Technology Dissidents, the Internet and Voting or Voting Machines.