Objectives. The largest increase of any ancestry group between the 1990 and 2000 Census in the United States were “unhyphenated Americans,” those whites who claimed an “American” or no ancestry. This article measures this group's voting habits in the 2008 elections.

Methods. With individual-level attitudinal data and county-level voting data from the 2008 primary and 2000–2008 general elections, the analyses use quantitative methods to estimate unhyphenated Americans' voting behavior.

Results. Evidence indicates a strong rejection of Obama among counties with high proportions of unhyphenated Americans in both the 2008 primary and general elections.

Conclusion. While spatially concentrated in and near Appalachia, unhyphenated Americans' politics are distinctive irrespective of socioeconomic status, religion, and geography, being one of the few groups in which Barack Obama lost votes compared to previous Democratic nominees. Variation in the share of unhyphenated Americans explains more of the difference between 2008 and past elections than variation in the share of African Americans per county.