Is it really true that candidates who are perceived as ideologically extreme do even worse if “they actually pose as more radical than they really are”?

Most of Kruggy’s column today is about macroeconomics, a topic I’m pretty much ignorant of.

But I noticed one political science claim:

It’s easy to make the political case that Democrats should nominate a centrist, rather than someone from the party’s left wing. Candidates who are perceived as ideologically extreme usually pay an electoral penalty; this is especially true if, like Bernie Sanders, they actually pose as more radical than they really are.

The research I’ve seen shows a small average electoral benefit for moderation (see here, for example), so I’m with the Krugmeister on that one. But where did he come up with the claim that extremists pay more of an electoral penalty if they actually pose as more radical than they really are? It’s hard for me to imagine there’s enough data to estimate that; also I’m not quite clear what the claim is, also I’m not sure how you’d go back and measure candidates’ posed and real ideologies. So all that makes me skeptical.

As always, I’d be happy to be corrected if there’s something I’m missing here.