It's a big stretch, because the guy despises the Democrats, but how about Howard Stern?
Stern could enter the Democratic primaries as an outsider who speaks his mind, is an egotistical media wh***, claims the party has abandoned and embarrassed the people, and runs as a champion of the people.
1. Experience playing the media and promoting himself? Check.
2. Gets away with saying outrageous things? Check.
3. Crass, vulgar and un-presidential? Check.
4. Wouldn't really belong in his party? Check.
5. Has had past political aspirations? Check.
6. Has massive "guy appeal?" Check.
7. Is kind of a bully? Check.
probably the best answer. And frankly, Trump's relationship with Republicans wasn't and still isn't all that great either so perhaps his anger at Democrats improves the analogy.