Now that you mention it, I just did a search as well, and it did turn up a few US pages which spelled the word without an aitch. Which is a little odd; as Emanuela noted in a message to me earlier, the aitch is needed in Italian to make the cc sound hard. The pronunciations of "gnocchi" and "Gucci" illustrate this phenomenon.

I wonder now, do the people who spell it that way pronounce "zuccini" with the "ch" sound found in "Gucci?" Or with the k sound found in "gnocchi?"