Chief Justice John Roberts, during arguments over the Voting Rights Act earlier in the week:
Is it the government’s submission that the citizens in the South are more racist than the citizens in the North?
Well, here’s what the 2008 American National Election Study had to say:

For more, see Sides, Bouie, and Valentino and Sears.
Update: Jessica Trounstine sends in this graph of several questions from the General Social Survey:

All data are from the combined 1998-2008 GSS surveys for non-Hispanic white respondents. The question wording is as follows:
- Work Way Up: Do you agree strongly, agree somewhat, neither agree nor disagree, disagree somewhat, or disagree strongly with the following statement: Irish, Italians, Jewish and many other minorities overcame prejudice and worked their way up. Blacks should do the same without special favors. (Graph shows proportion agreeing somewhat and agreeing strongly.)
- No Interracial Marriage: Do you think there should be laws against marriages between (Negroes/Blacks/African-Americans) and whites? (Graph shows proportion responding yes.)
- Blacks Shouldn’t Push: (Negroes/Blacks/African-Americans) shouldn’t push themselves where they’re not wanted. Do you agree strongly, agree slightly, disagree slightly, or disagree strongly? (Graph shows proportion agreeing strongly and slightly.)
- No Open Housing Laws: Which law would you vote for? A) One law says that a homeowner can decide for himself whom to sell his house to, even if he prefers not to sell to (Negroes/Blacks/African-Americans). B) The second law says that a homeowner cannot refuse to sell to someone because of their race or color. (Graph shows proportion selecting option A.)