When James Spader leaves that David Mamet drama after June 20, he will be replaced by Eddie Izzard, its producers said. Mr. Izzard, the comedian and actor who will take over in the role of the lawyer Jack Lawson, made his Broadway debut in the 2003 revival of “A Day in the Death of Joe Egg,” the Peter Nichols comedy; he’s also an Emmy Award winner for his comedy special “Eddie Izzard: Dress to Kill,” and looks smashing in drag (which he won’t be doing for “Race,” alas). “Race” is slated to run through Aug. 21 at the Ethel Barrymore Theater with a cast that will include Dennis Haysbert and Afton C. Williamson, as well as Richard Thomas, who has been in the play since its opening.