I posit that truly great scientists cannot make great politicians (at least in liberal democracies).
The primary motivation of a great scientist is to pursue truth, typically in what is observable or can be proven by experimentation (there are exceptions). The primary motivation of a great politician is to convince other human beings to affect change or keep them in office. This usually involves obfuscating truths and repainting what is observable to appeal to others.
This puts core motivations and corresponding skill-sets between a great scientist and great politician at fundamental odds with each other.
The primary motivation of a great scientist is to pursue truth, typically in what is observable or can be proven by experimentation (there are exceptions). The primary motivation of a great politician is to convince other human beings to affect change or keep them in office. This usually involves obfuscating truths and repainting what is observable to appeal to others.
This puts core motivations and corresponding skill-sets between a great scientist and great politician at fundamental odds with each other.