Living here in Utah among the large Mormon population presents us Catholics with many challenges and opportunities. Perhaps the greatest challenge is in the definition of terms, the Mormon church has co-opted the language of mainstream Christianity and changed slightly. When speaking with them, they often wait for the chance to jump at a position with cries of persecution. I have learned to define my terms and definitions at the begininning to prevent this from happening and foster good discussion. A charge often leveled at them is that their belief regarding God is polytheistic.
Strictly speaking, The Mormons are not polytheistic, and certainly not Monotheistic. They are Henotheistic.
Henotheism: The worship of a particular god without disbelieving in the existence of others. Random House College Dictionary