Washington (CNN) - Sen. Barbara Boxer, D-California, hopes to keep her seat. But a fresh poll suggests she may have a steep hill to climb.
In the latest Field Poll released Thursday, a slight majority of Californians hold a negative view of her.
Fifty-one percent view the senator unfavorably, with just 38 percent having favorable views of her. That's a 12-point jump in Boxer's unfavorable rating in the poll in January.
Meanwhile, Boxer appears to be losing ground in hypothetical match-ups between her and three potential Republican challengers: Rep. Tom Campbell, R-California, former Hewlett-Packard Chairman and CEO, Carly Fiorina, and Assemblyman Chuck DeVore.
According to the poll, there's a statistical tie between Boxer and Campbell, the same between Boxer and Fiorina, and Boxer leads little known Assemblyman DeVore, in the poll, by 4 points.
In January, Boxer held comfortable leads against her potential Republican rivals in the Field Poll.
As for where things stand for the Republican candidates vying for their party's nomination, the poll shows Campbell holding a 6-point lead over Fiorina and a 19-point lead over DeVore among the GOP voters. Those numbers have not changed significantly since January.
And though California voters more easily recognize Campbell and Fiorina than DeVore - the number of people who have no opinion of them remains high: 59 percent, 58 percent and 78 percent, respectively.