Little has changed in the 2010 U.S. Senate race in California over the past month, as incumbent Democrat Barbara Boxer maintains steady leads over two of the top Republican opponents.

A new Rasmussen Reports Election 2010 survey in the state shows Boxer leading former Hewlett-Packard CEO Carly Fiorina 46% to 37%. Five percent (5%) like some other candidate, and 12% are not sure how they will vote.

Last month both candidates earned slightly more support, when Boxer led Fiorina 49% to 39% LINK. Only 8% of voters were not sure of their choice in October.

In July, Boxer led Fiorina by just four but had a 47% to 38% lead in March.

Boxer leads state Assemblyman Chuck Devore 49% to 39% this month, after leading by nine in October. Five percent (5%) prefer another candidate while 13% are undecided.

Any incumbent who polls less than 50% is considered vulnerable, and 2010 is shaping up as a tough political year for Democrats. Still, Boxer, who is expected to seek a fourth term in the Senate next year, was reelected in 2004 with 58% of the vote, and California remains a heavily Democratic state.

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Twenty-four percent (24%) of voters share a very favorable opinion of Boxer, down three points from October. One in three voters (33%) now view her very unfavorably, up five points from last month.

Only 8% view Fiorina very favorably and 9% view her very unfavorably.

Just 4% view DeVore very favorably and 7% view him 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.

Fifty-one percent (51%) of California voters strongly or somewhat favor the health care reform plan proposed by President Obama and Congressional Democrats. While support among California voters for the plan is down four points from last month, it is still much stronger than support nationwide LINK. Forty-five percent (45%) in California now oppose the plan, including 37% who strongly oppose it.

In the race for California’s next governor in 2010, Democrat Jerry Brown and Republican Meg Whitman are tied at 41% each.

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