Americans are notoriously religious, which means that most believe in supernatural agents and forces. While most of these supernaturals are of the Christian variety, there seems to be a spillover effect. Belief in Christian supernaturals apparently doesn’t preclude belief in less orthodox kinds of supernaturals:
This isn’t surprising. Socially constructed and doctrinal lines separate “religion” and “spiritual” from “paranormal” and “magic.”
The common substrate is belief in the supernatural, which arises naturally from ordinary operations of the brain-mind. While these operations can be overridden, they rarely are because nearly all societies reinforce such beliefs with specific supernatural and religious content.