I'm not denying that he said it, I'm telling you that it was a JOKE. He was making a JOKE.
Have you ever been on a national tour? It's exhausting. You move through states and cities so fast, everything starts to look the same, and as fatigue sets in you lose track of where you've been, where you are, and where you're supposed to be next as everything starts to run together.
I mean, c'mon... He may be a alt-left wing socialist radical Saul Alinsky/William Ayers fanboy, but he knows how many states there are, for Pete's sake.