The largest group is "other" since the Daily Mail figures add up to about 240 out of 317 million Americans. Some 20 million now consider themselves simply "American", many of these formerly of "English" extraction. Heritage in order of size by millions:
German (49) Afro-American (41) Irish (35) Mexican (32) English (26) "American" (20) Hispanic/Spanish (18) Polish (10) French (9)
The map is coloured by "most named" heritage for every county in the U.S. It's astonishing how Germans, who never had a New World colony, are geographically represented the most. This doesn't mean in the majority in each county, just the most common. Also noteworthy are Black Americans in two northern cities and a band across the south.