Ellen DeGeneres will be honored with the Mark Twain Prize for American Humor on Oct. 22 at the Kennedy Center, and stars are lining up to be part of the tribute. So far Jimmy Kimmel, Kristin Chenoweth, Steve Harvey and Lily Tomlin have agreed to take part in the show, along with John Krasinski, Sean Hayes and Jason Mraz. The ceremony will air on PBS on Oct. 30.
