This question is mostly meant for fun, of course, but I have to say it's gotten me thinking.
By "equivalent" I guess I mean at least that the candidate should be famous, but not for politics. This list of liberal celebrities might be a good place to start.
Special bonus question for Democrats (and non-Americans sympathetic to US Democrats): This is the part that's really been haunting me, actually. Would you vote for that Trump equivalent, over a "serious" Republican candidate like Ted Cruz? As a Democrat myself, I have to confess I can imagine talking myself into voting for the totally unqualified candidate over the experienced Republican. But then I can't easily blame a Republican for doing the same ...