Hypothetically speaking, if Nazi's were still a major political force in Europe today, which groups would they be most likely to persecute?
Anyone deemed an enemy to the Reich. Hitler gave less of a damn about the science of "eugenics", as he cared for the political power that it allowed him to wield, to willingly discriminate against groups he saw as a threat. At various points in time, he would praise the Asians, the Muslims, among other ethnicities, and then denounce them, if they went against his will.
He would render any political enemy into an "untermensch", and praise any political ally as an "Aryan". The worst sub-humans, in his eyes, were the white European groups which supported Communism.
People forget that the first men to be purged were among his own (SA, Röhm, and all the left-leaning Nazis). Even his discrimination of Jews was calculated in the sense that the Jews were one of the richest demographics in Germany, and by removing them of their valuables (and eventually their lives, as well), he could use all of those riches to fund his conquests (which he did).
This was pretty similar to an old Roman tradition where aspiring military tyrants would often purge the rich, and rally the poor with promises of shared wealth, to fund their military endeavours. Hitler conducted himself like a Caesar, except not so merciful to his enemies.
Caesar himself had made himself wealthy by massacring hundreds of thousands of Gauls, including women and children.