This strikes me merely as bias. You can't see the distinctions or nuance in your opposition nearly so much as you can within your own camp. I for instance don't know of any conservative that thinks soros is behind every liberal/dem group or organization. I also don't know of any liberals that think the Koch's are behind everything on the Right, but in both cases I know folks who seem irrationally focused on either the Kochs' influence or Soros'.
Honestly, I see a lot more of the Crazy, OMG, the Kochs' talk than OMG, Soros.
Do you have a name? Becuase some guy who is supposedly a respectable Republican Congressman isn't exactly a convincing argument that Soro's hate is more mainstream than Koch hate.