HOLLYWOOD - RAGS-TO-RICHES drama 'Slumdog Millionaire' is the strongest best picture favourite in years while late actor Heath Ledger is all but guaranteed to win a posthumous Oscar at the 81st Academy Awards, bookmakers and pundits said on Friday.

With less than 48 hours to go until Sunday's show at the Kodak Theater in Hollywood, India-set feelgood movie 'Slumdog' is the overwhelming favourite according to bookmakers William Hill, which have priced the film at 1/10.

A spokesman for the betting firm said while there had been a burst of activity for 'The Curious Case of Benjamin Button,' "Slumdog' remained the 'massive, massive favourite'. 'It's always been our theory that at the end of the day Hollywood is about putting bums on seats and that this year, an uplifting feelgood movie like 'Slumdog' would be the clear favorite,' spokesman Rupert Adams told AFP.

'We think that they could put the statue on the chair for Slumdog Millionaire,' Mr Eckstein told AFP.

Joining 'Slumdog' as an Oscars certainty is 'The Dark Knight' star Ledger, set to become the first posthumous winner of an Oscar since Peter Finch for 1976's 'Network.' 'Heath Ledger is 1 to 40. These are the shortest odds that we ever had,' Mr Eckstein said. 'There's no chance the others will win. That category is over.' With the best picture race all but sewn up, pundits say the best actor and actress categories should provide greater suspense on Sunday.

Sean Penn, who plays trailblazing gay politician Harvey Milk in the biopic 'Milk' had been the long-time favourite but is adjudged to be narrowly trailing Mickey Rourke, the sentimental choice for his comeback performance as a washed-up prizefighter in 'The Wrestler.' 'Rourke is a very, very small favourite over Sean Penn, but we wouldn't be surprised if Sean Penn won,' Mr Eckstein said. 'They're very close in the odds and that should be very exciting.' -- AFP