State Polls: Promising Data Sources for Political Research

This research note suggests that the image of statewide polls as erratic bases for election predictions belies their reliability and usefulness as sources of information for basic scientific research. Data on partisanship from three different polling organizations, over a seven-year period, for fourteen different states, are presented to indicate that there is minimal interorganization variation among the three sources of data, a remarkable stability of sample estimates of partisanship within states through time, and a strong correlation between the state poll data and external validating indicators.