Scramble for the Senate.

Fiorina is increasing her efforts to reach out to Hispanic voters in California, speaking with Latino business community members in San Diego on Tuesday.

Some of her supporters were in San Diego as well, on a bus tour called "Vote Your Values," which has traveled through the state encouraging Latino voters to vote for Fiorina. The bus, sponsored by the Latino Partnership for Conservative Principles, stopped in Los Angeles Wednesday morning.

Meanwhile, Boxer, who received an endorsement from The Los Angeles Times Monday, became the target of a Spanish television advertising campaign launched by social conservatives. The ads, which will begin airing Thursday, will attack Boxer's stance on gay marriage and abortion.

Boxer leads Fiorina among undecided voters, according to a poll released Wednesday by USC's College of Letters, Arts and Sciences.

Both candidates continue to focus on Fiorina's past as CEO of Hewlett-Packard. Boxer say Fiorina outsourced thousands of jobs and nearly ruined the company, while Fiorina and her supporters maintain that she made a struggling company competitive again.

One of those supporters, former Alaska Gov. Sarah Palin, has officially endorsed Fiorina, but it could end up doing more harm than good. Almost sixty percent of voters in California have a negative opinion of Palin, and 53 percent of those surveyed said they would be less likely to vote for a candidate endorsed by Palin.

The candidates spoke separately Wednesday on NPR about their campaigns and the Nov. 2 election.

Reach associate news editor Taylor Freitas here. Follow her on Twitter: @taylorfreitas.

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