As part of our Red State, Blue State research, we developed statistical tools for estimating public opinion among subsets of the population. Recently Yu-Sung Su, Yair Ghitza, and I applied these methods to see where school vouchers are more or less popular.
We started with the 2000 National Annenberg Election Survey, which had responses from about 50,000 randomly-sampled Americans to the question: "Give tax credits or vouchers to help parents send their children to private schools--should the federal government do this or not?" 45% of those who expressed an opinion on this question said yes, but the percentage varied a lot by state, income level, and religious/ethnic group; These maps show our estimates:
Vouchers are most popular among high-income white Catholics and Evangelicals and low-income Hispanics. In general, among white groups, the higher the income, the more popular are school vouchers. But among nonwhites, it goes the other way, with vouchers being popular in the lower income categories but then becoming less popular among the middle class.
You can also see that support for vouchers roughly matches Republican voting, but not completely. Vouchers are popular in the heavily Catholic Northeast and California, less so in many of the mostly Protestant states in the Southeast. We also see a regional pattern among African Americans, where vouchers are most popular outside the South.
See here for more, including maps from 2004.