Some Democrats have speculated about Senator Dianne Feinstein entering this year’s race for governor in California, but former Governor Jerry Brown actually runs just a bit better against both of the major remaining Republican challengers in the race.

A new Rasmussen Reports telephone survey of likely voters in the Golden State finds Brown leading former eBay CEO Meg Whitman by four points, 43% to 39%. In November, the two were tied at 41% apiece.

Brown has a 10-point lead – 45% to 35% - over State Insurance Commissioner Steve Poizner. He led Poizner 43% to 32% in the previous survey.

Throw Feinstein in the mix, and the race becomes a bit more competitive. She essentially runs even with Whitman, leading the Republican by just one point, 43% to 42%. Feinstein leads Poizner by four, 43% to 39%.

In all these match-ups, anywhere from six percent (6%) to nine percent (9%) of California voters prefer some other candidate and roughly 10% are undecided.

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Another GOP contender, former Congressman Tom Cambpell, trailed Brown by nine points in November but has since quit the governor’s race to challenge Democratic Senator Barbara Boxer instead.

In the California Senate race, Boxer holds a narrow lead over Campbell and two other potential Republican challengers.

Voters not affiliated with either party prefer Whitman over Brown and both Republicans over Feinstein by double-digit margins. Against Poizner, Brown has a four-point edge among unafifliateds. In Massachusetts on Tuesday, unaffiliated voters favored the Republican candidate by a nearly three-to-one margin.

Men favor Whitman over Brown by 12 points and break even when Poizner’s the Republican in the race. Women support Brown over both Republican candidates by double-digits.

Against Feinstein, both GOP hopefuls carry male voters, while the Democratic senator leads among women.

Feinstein, who ran unsuccessfully for governor in 1990, has expressed no public interest in the governor’s race. Both parties will hold their primaries on June 8.

Twenty percent (20%) of voters have a very favorable view of Brown, while 22% regard him very unfavorably. Feinstein is seen very favorably by 28% and very unfavorably by 31%.

Whitman’s very favorables are 14%, her very unfavorables 10%. For Poizner, very favorables total eight percent (8%) and very unfavorables seven percent (7%).

Both Democrats as longtime statewide officeholders are much better-known than either Republican candidate.

At this point in a campaign, Rasmussen Reports considers the number of people with strong opinions more significant than the total favorable/unfavorable numbers.

Republican Governor Arnold Schwarzenegger is term-limited by law and cannot seek reelection next year. Only 29% approve of Schwarzennger’s job performance, while 72% disapprove. These numbers include give percent who Strongly Approve of the work he’s doing and 43$ who Strongly Disapprove.

Fifty-four percent (54%) of voters in California now approve of President Obama’s job performance, including 37% who Strongly Approve. Forty-three percent (43%) disapprove of how he is handling his job, with 35% who Strongly Disapprove. This is considerably higher than Obama’s job approval ratings in the Rasmussen Reports daily Presidential Tracking Poll.

Rasmussen Reports also has released data on the 2010 governor’s races in Arizona, California, Colorado, Florida, Massachusetts, Michigan, Minnesota, New York, Ohio, Pennsylvania, South Carolina and Texas.

In 2008, Rasmussen Reports projected nationally that Obama would defeat John McCain by a 52% to 46% margin. Obama won 53% to 46%. Four years earlier, Rasmussen Reports projected the national vote totals for both George W. Bush and John Kerry within half-a-percentage-point.

In California during the 2008 campaign, Rasmussen Reports polling showed Barack Obama winning the state by a 61% to 34% margin. Obama won 61% to 37%. Four years earlier, Rasmussen Reports polling showed John Kerry leading George W. Bush in California 53% to 43%. Kerry won 54% to 44%.

In the 2006 California governor’s race, Rasmussen polling showed Arnold Schwarzenegger defeating Phil Angelides 53% to 40%. Schwarzenegger won 56% to 39%. In the 2006 race for U.S. Senate, Rasmussen polling showed Dianne Feinstein defeating Richard Mountjoy 58% to 35%. Feinstein won 60% to 35%.

See all Rasmussen Reports 2008 state results for president, Senate and governor. See 2006 results for Senate and governor. See 2004 state results for president.

For Election 2010, Rasmussen Reports has released Senate polls for Arkansas, California, Colorado, Connecticut, Florida, Illinois, Kentucky, Missouri, Nevada, New Hampshire, North Dakota, Ohio, and Pennsylvania. A commentary by Larry Sabato, suggests that if the election were held today, “the Democratic majority in the Senate would be reduced to just 52 seats.”

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