The Democratic field is so wide that Saturday Night Live will likely have to bring in celebrity impressionists. Who else will play Bernie Sanders and Joe Biden other than Larry David and Jason Sudeikis, respectively? Kate McKinnon has already portrayed Elizabeth Warren, so she has that impression locked up. New cast member Bowen Yang seems like a sure thing to play Andrew Yang since they're both Asian-American. But what about Julián Castro, Kamala Harris, Beto O'Rourke, Pete Buttigieg, Marianne Williamson and Cory Booker?