Some people are trying to excuse their (or their organization) pass support for Nazi, one prominent cases in France is the "Front national" the 2nd biggest political organization atm, whose founder (the father of the current leader) was a Nazi sympathizer and occasional holocaust denier in more recent time. The idea goes something like "Yeah I supported the Nazi, but they really weren't bad people, they never killed that many Jew, those are just lies to discredit us/our idea".If the Nazis really do want to exterminate all Jews, wouldn't they just be up-front about it, not deny it, and explicitly claim that they'd like to do it again?
Or is the thinking that they're just being sneaky, pretending to be nice, and then, when they get power, drop the facade and do evil things?
If they've been denying that it happened all along...
People that support Nazi don't necesserly support wiping out other nationality, they might just seek preferential treatment for their group, with potential some form of system to just kick out the nationality they dislike. So someone could be Nazi sympathizer without being okay with the holocaust. Some people also, ridiculously, try to claim that the Jews were trying to revolt/take control of the country and that the holocaust was just a civil war and that the dead were enemy combatant.
I think it's ridiculous to equate denying the holocaust to making cartoon of the prophet and just goes to show how large the gap is (although personally I think neither should be illegal if one had to be illegal I think it goes without explanation why cartoon should not be the illegal one).