California, long a major cash source for candidates of both parties, is poised to become more influential in the electoral process as well, having moved its primary to next Feb 5. As a result, the state Democratic weekend convention was expected to attract all the party's major presidential contenders except Delaware Sen Joe Biden, who was campaigning in South Carolina.

Saturday's programme featured appearances by front-runners Clinton and Obama, as well as Connecticut Sen Chris Dodd and Ohio Rep. Dennis Kucinich.

Clinton unleashed an unusually personal critique of Bush, accusing his administration of ignoring scientific evidence about global warming and stem cell research and lying about the effects of toxic dust at the World Trade Centre site.

Her voice hoarse from days of campaigning, Clinton brought the 2,000 delegates to their feet when she said she wished she could turn the clock back to a different time.

"Somebody said to me that he wished we could just rewind the 21st century and just eliminate the Bush-Cheney administration, with all their mistakes and misjudgments," she said to cheers. "People are ready for leaders who understand it is our votes who put them in power, our tax dollars that pay the bills."