The appropriate answer here is Robinson, who is an actual polisci and who has coauthored all the stuff that acemoglu has published on institutions
Name them. To rule out cranks, another condition: they should also have demonstrated some promise of realizing their ambitions
I nominate KalyvasDaron Acemoglu
I know he is officially economist but most of his research is read and applicable to poli sci. Even many of his research could be easily published in poli sci journals.