One of the most interesting puzzles of this election cycle for both academics and pundits alike has been trying to explain exactly who exactly are all these Donald Trump supporters in the GOP voting base. Answers have focused on a variety of possible answers, including demographics, personality characteristics, and racial/identity attitudes. There is some evidence that there may be another factor at play, however: "American" ancestral self-identification.
The U.S. Census Bureau regularly asks Americans a version of this question: "What is this person's ancestry or ethnic origin? (For example: Italian, Jamaican, African Am., Cambodian, Cape Verdean, Norwegian, ... and so on.)" While most Americans indicate ancestries originating in Europe, Africa, or Latin America, in the 2010 Census about 20 million people (or 6.5 percent of the population) indicated "America" or "United States" as their place of "ancestry or ethnic origin." Most of these individuals are obviously not Native Americans, but rather white Americans who for one reason or another choose to report that their ancestors came from America. Some have referred to this group as "unhyphenated Americans" as they reject labels such as "German-American," or "Irish-American." (See here and here for more information.)
Scholars have offered a variety of causal factors related to this "unhyphenated American" phenomenon among white Americans including education, patriotism and national loyalty, Evangelical religious identification, or a perceived threat to American culture and identity. My own research (forthcoming in Social Science Quarterly) points to a strong influence of racial context and attitudes.
An examination of Census data reveals that the majority of these unhyphenated Americans are concentrated largely in the Southern and Appalachian regions of the United States:
Compare the map in the link above to the geographical distribution of Donald Trump supporters in the GOP electorate.
Of course, correlation is not causation and this possible connection is based entirely on aggregate data patterns making it impossible to conclusively link ancestral self-identification to voting patterns using only this information... but it is hard to ignore the similarities in the geographic concentration of unhyphenated Americans and Donald Trump supporters.
Donald Trump's campaign slogan has is "Make America Great Again." Perhaps this resonates with unhyphenated Americans who actively reject all non-American identities (even ancestral identities) and respond positively to his nativist, authoritarian rhetoric.