Incumbent Democrat Barbara Boxer is now in a virtual dead heat with former Congressman Tom Campbell in California’s U.S. Senate race.

The latest Rasmussen Reports telephone survey of likely voters in the state finds Boxer leading Campbell 43% to 41%. Six percent (6%) prefer some other candidate, and 10% are undecided.

A month ago, Boxer posted a 45% to 41% lead over Campbell.

Two other Republican hopefuls, former Hewlett-Packard CEO Carly Fiorina and State Assemblyman Chuck DeVore, remain within striking distance, but their numbers worsened very slightly this month.

Boxer now leads both Fiorina and DeVore by 46% to 40% spreads. Four percent (4%) opt for another candidate, and roughly 10% are undecided.

Voters not affiliated with either major party give a slight edge to Boxer in two of the contests but break even when Fiorina is the GOP candidate in the race.

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Boxer, who is seeking a fourth six-year term, has the power of incumbency on her side in a state that trends Democratic. But worrisome for her is her inability to rise out of the 40s where she’s been stuck for months while her opponents have been gaining ground. Incumbents who capture less than 50% of the vote at this stage of a campaign are considered potentially vulnerable.

The good news for Boxer is that support for the health care plan proposed by President Obama and congressional Democrats is stronger in California than it is nationally. That helps to explain why the anti-incumbency mood is slightly less pronounced in California than it is in many other states.

Fifty-five percent (55%) of California voters favor the Democrats’ health care plan, while 44% oppose it. These numbers include 32% who Strongly Favor the plan versus 38% who Strongly Oppose it.

As in the rest of the country, voters who Strongly Favor the plan overwhelmingly support the Democrat, while those who Strongly Oppose the plan just as overwhelmingly favor the Republicans in all three match-ups.

Fifty percent (50%) of all voters in the state agree that a better strategy for health care reform is to pass smaller bills that address individual problems rather than a comprehensive bill like the one now before Congress. But 40% think a comprehensive bill is better.

Unlike in many states, the plurality (49%) in California fear private health insurance companies more than the federal government when it comes to health care decisions. Forty-six percent (46%) fear the government more.

Forty-three percent (43%) say the president is doing a good or excellent job handling health care reform. Thirty-nine percent (39%) rate his performance as poor.

Fifty-nine percent (59%) of voters in the state say it would be better for the country if most incumbents in Congress were defeated this November. Twenty-two percent (22%) disagree and say it would be better if most were reelected.

But 39% say their local representative in Congress deserves to be reelected, while 35% think otherwise.

Thirty-four percent (34%) have a favorable view of the Tea Party movement, but 40% view it unfavorably. Eighteen percent (18%) of California voters describe themselves as a part of that movement.

Troubling for Boxer is that while 19% of the state’s voters have a very favorable opinion of her, 32% view her very unfavorably.

Campbell is viewed very favorably by 14% and very unfavorably by 11%.

For DeVore, very favorables are four percent (4%) and very unfavorables are nine percent (9%).

Eleven percent (11%) regard Fiorina very favorably, while 14% view her very unfavorably.

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

State Republicans will pick their nominee in a June 8 primary.

Despite the state’s well-publicized budget problems, 50% of California voters think the economy will be stronger a year from now. Twenty-seven percent (27%) expect it to be weaker, and 18% say it will stay about the same.

Yet just 26% say it now possible for anyone who really wants to work to find a job. Fifty-nine percent (59%) disagree and say it’s not possible.

Obama won California in 2008 with 61% of the vote, and he remains popular in the state. Fifty-eight percent (58%) approve of the job he is doing as president, with 31% who Strongly Approve. Forty-two percent (42%) disapprove of the president’s job performance, including 34% who Strongly Disapprove. This gives Obama a job approval rating in California that is much better than findings nationally in the Rasmussen Reports daily Presidential Tracking Poll.

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 Obama winning the state by a 61% to 34% margin. He 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.

Rasmussen Reports also has recently surveyed Senate races in Arkansas, Colorado, Illinois, Indiana, Kentucky, Louisiana, Maryland, Missouri, Nevada, New Hampshire, New York, North Carolina, North Dakota, Florida, Connecticut, Pennsylvania, Oklahoma, Ohio, Oregon, Washington and Wisconsin.

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