You know how a lot of Americans say that they are part Irish, Italian, German etc.
I don't think I've heard many Americans say that they have Spanish roots, unless they do the thing where some Americans also include Latin America into the word and mean the whole Spanish-speaking world and they include puerto ricans, mexicans, cubans etc.
Most Spaniards went to Spanish-speaking countries, but are there not that many with Spanish roots in the US? Obviously there is at least one person with it, but I mean with the same size as Americans with German, Irish roots etc.