.ca is for Canada and is administered in Canada - to circumvent that and pretend it's for California makes no real sense.
So it is for .al .ma and all the country extentions. They are claimed and not US facing.
Instead I think that you may see the rise of the specialised domain extentions where you can have a word as the TLD.
(see
http://www.titaninternet.co.uk/domains/gtlds.cfm for some current ones).
So Alabama might be
.bama, while Maine doesn't need to shorten and could be
.maine etc. Each state will come up with an extention for localised use. It might take 3-5 years but I could see
waterparks.cali or
casino.vegas being easy to remember destination sites,