Inconsistency between an achieved and an ascribed status is more likely to lead to Democratic party preference than is inconsistency between two achieved statuses. Because members of the present generation are more likely to attain their occupations through achievement than were their fathers, intergenerational mobility in many cases leads to achievement-ascription inconsistencies. Our data show that both the upwardly mobile and the downwardly mobile are likely to support the Democratic party, thus helping to explain part of the partisan realignment in the United States favoring that party.