Polls and Elections Preelection Poll Accuracy and Bias in the 2012 General Elections

This report examines accuracy and bias in national and state‐level preelection polls conducted during the 2012 general election cycle. Overall, polls in 2012 were somewhat less accurate than in previous cycles, and especially as compared to 2008, and tended to overestimate Republican support at the polls. Nevertheless, these biases were generally statistically insignificant, suggesting significant bias in preelection polls was scarce in 2012. This was generally true of polls for all national and statewide contests, survey modes, sample types, time period, and survey organizations.