I'd rally the remaining normals and start a war of extermination against the muties. It'd be either them or us, and I think we might have a fighting chance if they rely on their superpowers too much and fight without technology. If they do though, I think that "rebellion" would be doomed.
Edit: Just to explain why I'd do that: I'm relatively sure that the people with super powers would think of themselves as a sort of master race and society would be split into two casts, the "normals" and the muties and the normal people would be suppressed.