Compared to historians and scholars dealing with Jesus mythicists, those who tackle other forms of denialism seem to have it somewhat easier – or would, if denialism could be combated with logic of the sort illustrated in this XKCD cartoon:
In related news, while I myself have used the comparison between the tactics used by Jesus-mythicists and Holocaust-deniers, I agree completely with Matthew Paul Turner that it is in bad taste to make the comparison as a response to visiting a Holocaust exhibit. It is not that the comparison does not make a valid point, but there is a moral atrocity in denying the reality of the Holocaust that simply is not matched in Jesus-mythicism.