Billionaire Republican Meg Whitman has built a slight lead in the California governor's race after contributing a record-breaking $39 million to her own campaign, a Los Angeles Times/USC poll showed on Monday.

The former CEO of online auction house eBay Inc., making her first bid for elected office, has 44 percent of the vote to Democratic candidate and former governor Jerry Brown's 41 percent, according to the poll for the November election.

The winner will succeed Governor Arnold Schwarzenegger, who is barred by term limits from seeking re-election.

In what is expected to be the most expensive nonpresidential election in U.S. history, Whitman has spent millions on television ads ahead of the June primary and holds a 40-percentage point lead over Republican Steve Poizner.

"The story is the money. The amount of money and the level of advertising Whitman has run to date is not only unprecedented ... it has had a very clear marked effect on campaign," said Dan Schnur, director of the Jesse M. Unruh Institute of Politics at the University of Southern California.

"Among people who have seen her ads, Whitman is beating (Brown) handily, but she's losing to those who have not seen them," Schnur said.

Whitman's $39 million contribution is a record in California for candidates donating to their own campaigns.

More than seven months ahead of the general election, she has spent $46 million, a record for a candidate in a California statewide election and more than Schwarzenegger spent in his entire 2006 campaign.

In the U.S. Senate race, California Democratic incumbent Barbara Boxer has a comfortable lead over a "generic Republican", with 48 percent of the vote to 34 percent, despite a drop in popularity as she seeks a fourth term.

But the pollsters said that voter anger could make the race one of Boxer's toughest reelection campaigns.

"The most striking thing to me (about the poll results) is how bleak the view of the economy is and how bleak the view of state political leaders and institutions is, and that clearly is driving everything," said Stan Greenberg, CEO of Democratic Polling firm Greenberg Quinlan Rosner.

"You get very little expectation of change in the coming year which is not consistent with what you see nationally," Greenberg said. "Where there is some optimism (nationally), that optimism is not there in California."

Former Hewlett-Packard CEO Carly Fiorina trails former U.S. Representative Tom Campbell in the race to secure the Republican nomination to challenge Boxer, with 25 percent to his 29 percent, the poll showed.

The poll surveyed 1,515 registered voters between March 23-30 with a margin of error of plus or minus 2.6 percentage points.

Reuters