If you are a Democrat, would you marry a Republican? Would you be upset if your sister did?
Researchers have long asked such questions about race, and have found that along important dimensions, racial prejudice is decreasing. At the same time, party prejudice in the U.S. has jumped, infecting not only politics but also decisions about dating, marriage and hiring. By some measures, "partyism" now exceeds racial prejudice -- which helps explain the intensity of some midterm election campaigns.
