LOS ANGELES, California (AP) - Jack Nicholson's Joker was a blast. Heath Ledger's Joker is as dark and anarchic a figure as Randle McMurphy in "One Flew Over the Cuckoo's Nest," the role that brought Nicholson his first Academy Award.

Many movie critics say Ledger's performance in the Batman tale "The Dark Knight" is so remarkable that next January 22, the one-year anniversary of his death, he could become just the seventh actor in Oscar history to earn a posthumous nomination.

Superhero flicks usually are not the stuff Oscar dreams are made of. Yet Ledger delivered so far beyond anyone's expectations that he could end up as the second performer to win Hollywood's top honor after his death.

"He may be the first actor since Peter Finch. He may even win the damn thing," said Gary Oldman, who co-stars as noble cop Jim Gordon in "The Dark Knight," which hits theaters July 18.

Finch is the only person to win posthumously, earning the best-actor prize for 1976's "Network" two months after he died.

Along with Finch, past posthumous Oscar contenders include James Dean, who was nominated for best actor twice after his death, with 1955's "East of Eden" and 1956's "Giant."

News of Ledger's death at age 28 from an accidental drug overdose broke just hours after the Oscar nominations were announced last January, darkening what normally is one of Hollywood's happiest days.

With a marketing campaign heavily focused on the Joker, the movie trailers that followed presented a Joker with sloppy, ominous clown makeup that looked as though it had been applied in a windstorm. The brief footage revealed a character whose cackling humor cannot conceal the malevolent soul beneath.

"Whatever Heath channeled into, he's found something quite extraordinary," Oldman said. "It's arguably one of the greatest screen villains I think I've ever seen."

Warner Bros. and the filmmakers are profuse in their praise of Ledger but have been diplomatic about the Oscar talk. Awards publicity generally pads a movie's box-office and DVD receipts, and the studio has cautiously avoided any appearance of profiting from the added attention Ledger's death has brought to the film.

"The Dark Knight" director Christopher Nolan sidestepped the Oscar question, saying that he was simply happy that early viewers were responding to the performance the way Ledger would have liked.

(Copyright 2008 by The Associated Press. All Rights Reserved.)