S.P.
I like Schramsberg too, and have done well with california and even oregon "sparkling wines" done with the champagne method.
I remember drinking Gloria Ferrar, oh and so many others... You are sending me down memory lane to the days when a typical sunday was whiled away with champagne and popovers - the days before kids!
By the way, the poster who said that it is wine to which carbon dioxide has been added is not correct. I believe that is soda. They do some different kind of yeast and fermenting to create the bubbles.
But she is correct that only sparkling wine produced in the Champagne region of France (and generally with champagne grapes) can properly be called champagne. All others are "just" sparkling wine. But unless you are a French marketing rep, you probably don't care, you just want something that tastes good. You live in California, so you should have lots of inexpensive choices that are wonderful.