Who should play Frank Sinatra?

Martin Scorsese will direct an upcoming biopic on the life of Frank Sinatra. Now the big question is, who's going to play ole' blue eyes on the big screen? Johnny Depp, George Clooney, and Leonardo DiCaprio are all said to be in the running. Who do you think should be cast in the role? Out of all of them, George is the most suave, but he's too old to play Sinatra during his younger years, as is Johnny Depp. (Sorry, guys!) Martin Scorsese loves Leo, so my guess is that he'll be the one case in the film, but can Titanic Boy sing? Hmm...I can't recall him ever singing in a film. Maybe they'll cast an unknown in the part. That would probably be best.

Who would you pick to play Sinatra in a movie?