Not more than they would if they weren't persecuted. I am certain neo-nazis would much prefer to spread their hate as publicly as possible through Sunday morning cartoons and flyers and ads, and the fact that we as a society have restricted them from doing so has weakened, not strengthened them.

Maybe some people find a morbid attracting to them as a result of them being forbidden just for this reason. But for the large majority, this has not happened.