Gov. Arnold Schwarzenegger's image and job rating appear to be rebounding with voters, according to a new poll released Tuesday that shows the Republican governor leading Democratic state Treasurer Phil Angelides by 8 percentage points.

The Field Poll found 45 percent of likely voters surveyed favored Schwarzenegger, with 37 percent backing Angelides.

Nearly half the 731 likely voters surveyed approved of Schwarzenegger's job performance, the first time since February 2005 that more voters approved than disapproved of the job he is doing, the Field Poll found.

And for the first time since September 2004, more voters rated as positive the direction the state is heading than said it was negative. Schwarzenegger's star had faded last year after voters defeated all his initiatives in his November special election.

The campaign this year has been a referendum on Schwarzenegger, the Field Poll found, with two-thirds of Angelides backers saying their support is a vote against the governor rather than an endorsement of his Democratic challenger.

Some Republicans have criticized Schwarzenegger as too liberal, but the poll found he nonetheless enjoys support from 85 percent of those voters who called themselves Republicans. Sixty-three percent of Democrats said they support Angelides after a bruising primary fight with state Controller Steve Westly.

The telephone survey, conducted July 10-23, had a sampling error rate of plus or minus 3.8 percentage points.

It showed 15 percent of voters were still undecided and 3 percent backed other candidates.

Another poll released Monday found the candidates about even. The Zogby poll found 44 percent support for Angelides and 42 percent for Schwarzenegger, but it was within the poll's sampling error margin of plus or minus 3.5 percentage points. That survey was conducted from July 11-19.

Angelides' media consultant, Bill Carrick, noted that Schwarzenegger has spent more than 10 times as much on advertising as his rival since the June primary election — $15 million for Schwarzenegger compared with $1.4 million for Angelides.

"Clearly, the Schwarzenegger campaign attempted an immediate post-primary knockout punch of Angelides," Carrick said. "They swung and missed."

Support under 50 percent is bad news for an incumbent governor, and Angelides' numbers will likely rise among Democrats and other voters as they learn more about him, Carrick said.

Katie Levinson, Schwarzenegger's communications director, said voters "are rejecting Phil Angelides' negativity and pessimism and his call for a $10 billion tax increase. ... In contrast, we continue to see Californians respond positively to the governor's positive vision for California."