LOS ANGELES - American Idol is back and bigger than ever.

The Fox TV talent contest's season premiere was the most-watched in its six-year history, drawing an estimated 37.3 million viewers in the United States Tuesday, according to preliminary ratings from Nielsen Media Research.

In addition, the show -- broadcast in Canada by CTV -- had an average audience of just over three million, peaking at 3.6 million.

The U.S. figure represents a five per cent increase over last year's record premiere audience of 35.5 million, qualifying it as the best debut ever for Fox, the network said. Final ratings will be released next week.

"American Idol continues to make entertainment history,'' Simon Fuller, the series' creator and executive producer, said in a statement Wednesday. "These amazing numbers from our season-6 premiere defy all reasonable expectations.''

The top-rated show, which also airs Wednesday, is breaking television's laws of gravity that bring declining viewership for aging shows.

It's received a boost from its high-profile alumni, including hot recording stars Kelly Clarkson and Carrie Underwood and "Dreamgirls'' star and Golden Globe winner Jennifer Hudson.

American Idol, which gives viewers the chance to pick the finalists and winner, began as usual with scenes from U.S.-wide auditions. The early rounds feature both promising singers and those who serve as targets for acerbic judge Simon Cowell before they're booted out.