A new poll shows Sen. Barbara Boxer (D-Calif.) falling further behind Republican Senate candidate Carly Fiorina.

The SurveyUSA poll has Fiorina leading Boxer 47 percent to 42, compared to a July survey for the same San Francisco CBS affiliate that showed Fiorina ahead of Boxer by just a couple points.

The poll's release comes as AFL-CIO chief Richard Trumka is set to hit Fiorina as a "clueless" CEO in a speech in Los Angeles on Friday. President Obama will also be back in the city on Monday for fundraising events for the Democratic Congressional Campaign Committee.

Meanwhile, Fiorina's campaign said the survey results were a sign voters were "unsatisfied" with Boxer.

"Despite her high name recognition and clear advantage when it comes to party registration in California, she is seeing her support shrink just 82 days from Election Day, and that's a trend we anticipate will continue," Julie Soderlund, a spokeswoman for Fiorina, said in a statement.

Boxer's camp admitted she's facing a "tough race.


"Carly Fiorina has been attacking Barbara Boxer every day to distract voters from her terrible record at HP, where she laid off 30,000 employees and shipped jobs to China, all while taking more than $100 million in bonuses and perks for herself," Rose Kapolczynski, Boxer's campaign manager, said in a statement. "When the voters learn about the clear choice in this race, they will choose Barbara Boxer."