Why bother with a professional politician? Bill Clinton was probably the most polished and at least reasonably accomplished professional politician they have run in 50 years. Not that I agreed at all with him, but at least he was governor & attorney general. Kerry & Gore, Carter, Mondale & Dukakis had at least a modicum of a political resume.
Go with the Oprah! Maybe add another no political experience goofball for continuing humor.