Why stop at Puerto Rico? Add Guam, the Virgin Islands, and the Northern Mariana Islands as well for another 6 Senate seats.
Isn't there a requirement for states to have a certain population? 100,000 or so?
No, but there's generally been a rough guideline of having enough population to get a Representative even without the guaranteed minimum of one. DC and PR are the only territories to meet the traditional population criteria. For many years Nevada was the exception that proved the rule. Nevada got admitted early because of projections it would quickly grow up, but then it failed to grow and even shrank. Arguably it should have been our 50th state (admitted 1960), and Hawaii our 48th (admitted 1912 or so).
