"*Obama, who is of mixed heritage, is widely referred to as the first African American to be elected President of the United States. — Out of the lot of more or less workable compromise, this is the best I can currently think of. It accounts for the fact that Obama is indeed African American, according not only to self-identification but also to the commonplace definition (whence the link to Multiracial American#African Americans). It also lends some explanation to why we (more or less rightly) assign so much weight to this statement as to make it the second sentence of the lead, namely that apart from the fact that Obama is African American (which by itself is a tidbit of minor relevance in the greater shape of things), he is also and importantly widely being referred to as [...]. Everyme 

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