[ifelsehow]

That's 26% of US states, but potentially much more than 26% of the US population (have not computed, but Texas, New York, Florida and, to a lesser extent, Washington all have large populations).

[moojd]

5/10 of the most populous states

2. Texas

4. Florida

5. New York

9. Georgia

10. North Carolina

A quick check to https://en.wikipedia.org/wiki/List_of_states_and_territories... gave me ~38% of the US population