This is for those who have already obtained a visa (in America) and are RENEWING to return to Spain. The question is ‘Do I have to go back to my state’s consulate and go through the hassle of getting another visa?’

Answer:

NO,

if you complete a little paperwork here in Spain.

If you plan to go outside Spain (outside the European Schengen zone) while your identity card is expiring, you must legally obtain what is called an Autorizacion de Regreso. If you leave the zone for more than 90 days, you legitimate have to repeat the visa process.

Again, the answer to the question about getting another visa is

YES

if you leave for more than 90 days (or do not take care of the paperwork to renew your identity card and your so-called Estancia).

For beginners: Get a visa.