Mark Blumenthal believes the Quinnipiac poll in Pennsylvania has an excellent record. Some analysis of the internals here. One nugget:
Hillary Clinton's unfavorable rating among African Americans (34%) is now greater than Obama's unfavorable rating among non-college educated whites (26%).
This article available online at:
http://www.theatlantic.com/daily-dish/archive/2008/04/parsing-quinnipiac/218168/
