Sen. Barbara Boxer (D-Calif.) is polling under 50% in a new Rasmussen poll (Jan. 14, 500 LV, MoE +/- 4.5%), which finds her leading three potential Republicans in general election matchups. Ex-HP CEO Carly Fiorina and ex-Rep. Tom Campbell, who just joined the race, perform nearly identical against Boxer, while conservative Assemblyman Chuck DeVore is just 6 points back.

Boxer 46 - Fiorina 43 - Und 8

Boxer 46 - Campbell 42 - Und 9

Boxer 46 - DeVore 40 - Und 10

Boxer, running for her fourth term, fails to exceed 46% against any of the three Republicans -- not a good sign for any incumbent. Forking out $14 million in 2004, Boxer doubled her opponent's spending and won by 20 points. The seat hasn't been held by a Republican in 42 years.

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