The Wikipedia page on which the above map appears also has two other maps which show English ancestry among Americans. As the Wikipedia article rightly points out, though, the data may represent an undercount, based partly on self-reporting, and as the article says, many Americans who are partly of English ancestry, maybe even predominantly so, identify with more recent immigrant ancestry, especially if that ancestry is of a type considered more ”vibrant” and colorful. The more exotic or far-removed from Northwest Europe, it seems, the more likely the individual will identify as that ancestry first.
Considering the fact, too, that most Americans have rather insubstantial data on their ancestry, except of course for those whose forebears arrived in this country more recently. Until or unless most people get DNA testing done (and I am not wholly convinced that the private DNA testing firms are reliable) we can’t be sure of the ethnic makeup of this country.
Oddly enough, Utah appears to be the state which has the greatest percentage of English descent, and I would surmise that is because the Mormons who settled that state were often people of Midwestern origin whose forebears moved West from New England when that area began to be settled by the 19th century immigration wave. And many of Utah’s original White settlers came directly from New England.
The area which should have higher percentages of English ancestry is probably the South. It used to be an accepted fact that the South was primarily Anglo-Saxon, or Anglo-Norman, as the old families of the South asserted, but in recent years it has become more popular to claim Scots-Irish ancestry.
There are fads and fashions in ancestry as well, it seems. Sometimes it’s just not ”in” to be of a certain ancestry.