Trying to find this one for someone on another site. The plot synopsis as we both remember it is that a man has mental powers probably controlling type, gets into see the President and as he is leaving he's whacked on the head with a hammer and killed. My additional memory is that someone says: "He never said he could read minds."
I also remember the artwork illustrating the story because I cut it out and used it on a collage.
Pretty sure it was in Playboy but a search of published short story titles rang no bells.