If the two rookie candidates make it past Tuesday's primaries, can they take on career politicians and win office?
Both women are willing to bet their personal fortunes they can.
Would-be California governor Ms. Whitman promises to chop the state budget by $15-billion (U.S.), but the former eBay boss has shown no appetite for fiscal self-restraint in her quest to win the Republican nomination.
The billionaire front-runner in Tuesday's GOP gubernatorial primary has spent an estimated $70-million of her own money to saturate the California airwaves with ads that, among other things, portray her as "tough as nails" on illegal immigration.
Her almost equally wealthy opponent, Steve Poizner, has spent a "mere" $25-million of the personal stash he accumulated as a Silicon Valley entrepreneur to run ads that, unsurprisingly, depict Ms. Whitman as a "liberal" who "supports Obama's amnesty plan."
Both of them make Ms. Fiorina, the ex-Hewlett Packard chief who is seeking the Republican Senate nomination, look downright frugal with out-of-pocket primary spending of about $6-million. But, then again, her net worth has only nine digits, not the 10 of Mr. Poizner and Ms. Whitman.
What all three candidates have in common, however, are their deep-throated expressions of conservative values as they court Tea Party enthusiasts and other Republican malcontents determined to impose their will on the GOP.
But while the influence of Tea Partiers and their ilk will certainly help determine who carries the Republican banner after Tuesday's primaries in 10 states, it could also doom the GOP in November's mid-term congressional elections if the party's radical-right branding alienates centrist voters.
Republicans could find themselves snatching defeat from the jaws of victory in California, where the state budget crisis and 12.5 per cent unemployment rate have hurt Democrats most. Incumbent Democratic Senator Barbara Boxer is seen as so vulnerable that President Barack Obama has travelled twice to California in recent weeks to rally donors and grassroots Democrats on her behalf.
But the 55-year-old Ms. Fiorina, who opposes abortion and gay marriage, has tacked far to the right during her primary campaign to capture some Tea Party support. She has also played up an endorsement from Sarah Palin. And she has run TV ads attacking Ms. Boxer for calling climate change an important national security issue.
"Terrorism kills. And Barbara Boxer is worried about the weather," Ms. Fiorina, who recently overcame a bout with breast cancer, scoffs in the ad. "I'll work to keep you safe."
While all that seems to work well in the Republican primary - Ms. Fiorina has pulled solidly ahead of centrist candidate Tom Campbell - it could prove fatal in the fall as Ms. Fiorina tries to capture independent voters. No anti-abortion candidate has won a major state or national office in California in more than two decades. And if climate change still has a constituency in the United States, it is found in places such as California.
"If I look at Senate and governor's races, they tend to be determined by the ability of a candidate to define themselves as being in the political centre," Mark Baldassare, president of the Public Policy Institute of California, said in an interview. "The successful candidate is the one who is able to say their opponent is either too conservative or too liberal."
Ms. Whitman, 53, had tried to focus her primary campaign almost exclusively on fiscal issues as the California legislature bickers over how to close a $19-billion budget shortfall by July 1.
Mr. Poizner, however, drew her into a debate on immigration after Arizona's April passage of a tough new legislation to root out illegal migrants. Ms. Whitman felt vulnerable enough to launch ads declaring her "100 per cent against amnesty" for illegal immigrants.
"As governor, I will crack down on so-called sanctuary cities like San Francisco who thumb their nose at our laws. Illegal immigrants should not expect benefits from the State of California," she insists in the ads.
Such talk does nothing to ingratiate Republicans to Hispanics, who make up 37 per cent of California's population. Non-Latino whites now account for a minority - 42 per cent - of the state's 37 million residents. And though white Californians are expected to account of two-thirds of voters who turn out this fall, Hispanic support is increasingly key in state-wide races.
Should they prevail as in their respective primary races, Ms. Whitman and Ms. Fiorina will likely attempt to refocus their campaigns on economic issues, attacking Ms. Boxer, Mr. Obama, Congress and the Democratic majority in the state legislature where they are most vulnerable.
"If there is one issue on which Californians are conservative, it's taxation. California has been in a state of constant tax revolt since 1978," noted Bruce Cain, a political science professor at the University of California at Berkeley.
Since that year's successful ballot initiative, Proposition 13, property taxes have been capped and state-wide tax increases must be approved by a two-thirds majority in both houses of the legislature. Current Republican Governor Arnold Schwarzenegger has proposed closing the budget gap without increasing taxes largely by slashing social programs and education.
Californians will likely have to decide this fall whether to next entrust the gubernatorial scissors to a rookie politician such as Ms. Whitman or opt for a veteran in Jerry Brown, the 72-year-old former Democratic governor and current state attorney-general, who now wants his old job back.
As Prof. Cain explained, it's not an easy choice: "We're just coming off a governor who had to learn on the job. The question is whether we want to do that again."