Brokeback Mountain has won the Producers Guild of America's top award, a prize that often indicates Academy Award success.
Brokeback Mountain stars Jake Gyllenhaal and Heath Ledger
Film-makers Diana Ossana and James Schamus, who produced the story of the love that develops between two cowboys, took home the guild's top prize.
In 11 of the past 16 years, the guild has honoured films which have gone on to win the best picture Oscar.
Wallace & Gromit: The Curse of the Were-Rabbit won best animated film.
The film earned Wallace and Gromit creator Nick Park and Claire Jennings the producer of the year award for animated film.
HBO's The Life and Death of Peter Sellers was named best made-for-TV film, ABC's Lost was named best TV series and HBO's Entourage took best TV comedy series honours at the Los Angeles ceremony on Sunday.
Lost follows plane crash survivors who are stranded on a desert island
Brokeback Mountain, starring Heath Ledger and Jake Gyllenhaal, took won four Golden Globes last week, including best picture honours.
But Ledger lost out on the best dramatic actor award to Philip Seymour Hoffman, who won it for Capote.
The other contenders for the PGA were Capote, Johnny Cash biopic Walk the Line, Good Night and Good Luck, and Crash.
The producers are the first of the US craft guilds to name their best picture ahead of the Oscars on 5 March.
The Screen Actors Guild Awards will be handed out at a ceremony in Los Angeles on 29 January, the day after the Directors Guild of America's ceremony.
This year's Oscar nominations will be announced on 31 January.