Newport Beach, Calif.—Carly Fiorina, 55, has been contending with chemotherapy and radiation treatments and reconstructive surgery because of breast cancer, so she is understandably undaunted by the relatively minor challenge of winning a U.S. Senate seat in this state that last elected a freshman Republican senator in 1982, that has not supported a Republican presidential candidate since 1988, and that has not elected a right-to-life candidate in statewide voting since 1998. This race will test the power of the rising Republican wave.

Fiorina might surf it from here to Capitol Hill because her opponent, Barbara Boxer, 69, is the Senate’s fiercest liberal, and California is an intensely unhappy laboratory for liberalism—high taxes, opulent entitlements, thick regulations, and subservience to government employees’ unions.

During 10 years in Congress, Boxer represented San Francisco suburbs where many residents consider the city’s liberalism too tepid. She is used to having the wind at her back. In 1992, California’s “year of the woman,” she ran for the Senate in tandem with Dianne Feinstein, who won the final two years of the Senate term Pete Wilson left when he became governor. Boxer was reelected in 1998 when California was luxuriating in the tech boom. In 2004 she won when John Kerry was trouncing George W. Bush in the state by 10 points. Now the 28-year Washington veteran seeking a fourth term is running into headwinds.