Sure, people from Pennsylvania are Pennsyvanians, NY are New Yorkers, Texas are Texans, but what do you call people from Utah? Or Maine? Or Vermont? Arizona? Wyoming? Colorado? Heck, what about people from Guam?
Just add ers and Ian's at the end and bobs you uncleian.
Utahan (U-tah-in)
And most english speakers say "Guamanian" but the natives call themselves Chamoru or Chamorro.