Theistic and analytic philosophers of religion typically privilege classical theism and monotheism by ignoring or underestimating the great threat of polytheism. We develop an argument from infinitely many alternatives, which decisively demonstrates that if a monotheistic or polytheistic god-model obtains, it will almost certainly be polytheistic. Probabilistic calculations are performed in order to illustrate the difficulties faced by the monotheistic proponent. After considering possible objections, such as whether there should be limits placed on how many possible god-models could obtain, we (...) conclude that our argument from infinitely many alternatives is sound, and highly unlikely to be overcome. (shrink)