I can't think of anyone but this is making me wish that I could remember some of the estimates that I have seen for share of the US population with pre-1776 ancestry. By the time you have accounted for colonists, people held as slaves, and native populations, IIRC it remains a strong majority well into the twentieth century.
Not sure about 1776, but there is a commonly-cited estimate that the fraction of the US population which had ancestry in the US dating to before the 1790 Census did not fall under 50% until the 1990 Census:
https://www.discovermagazine.com/the-sciences/when-america-was-post-colonial
