I missed this new paper from William Hicks, Seth McKee, Mitchell Sellers, and Daniel Smith.
We undertake a comprehensive examination of restrictive voter ID legislation in the American states from 2001 through 2012. With a dataset containing approximately one thousand introduced and nearly one hundred adopted voter ID laws, we evaluate the likelihood that a state legislature introduces a restrictive voter ID bill, as well as the likelihood that a state government adopts such a law. Voter ID laws have evolved from a valence issue into a partisan battle, where Republicans defend them as a safeguard against fraud while Democrats indict them as a mechanism of voter suppression. However, voter ID legislation is not uniform across the states; not all Republican-controlled legislatures have pushed for more restrictive voter ID laws. Instead, our findings show it is a combination of partisan control and the electoral context that drives enactment of such measures. While the prevalence of Republican lawmakers strongly and positively influences the adoption of voter ID laws in electorally competitive states, its effect is significantly weaker in electorally uncompetitive states. Republicans preside over an electoral coalition that is declining in size; where elections are competitive, the furtherance of restrictive voter ID laws is a means of maintaining Republican support while curtailing Democratic electoral gains.