SACRAMENTO - To her boss she is a genius and a ``machine.'' To her detractors she is a cool outsider who is out of touch with California.

But both sides agree that Gov. Arnold Schwarzenegger's budget guru, Donna Arduin, has arguably the toughest job in Sacramento -- to fix the state's budget in a Capitol that is deeply polarized over the best course to follow.

Arduin, who inherited her affinity for numbers from her accountant mother, has worked for three Republican governors and has a reputation for shrinking government and privatizing public services. Her views are revered by fiscal conservatives and feared by liberals.

How she will fare in Sacramento, where Democrats control the Legislature, is uncertain. Arduin is expected to be confirmed by the Senate this week, with minimal fuss out of courtesy to the Republican governor.

In bodybuilding and now in politics, Schwarzenegger has been known to keep his opponents off balance. Many in the Capitol consider Arduin the hard-nosed foil to the governor. They say her tough conservative line allows Schwarzenegger to play the accommodating moderate in negotiations with Democrats.

``She is the conservative conscience of the administration,'' Senate Republican Leader Jim Brulte said.

Or as another Republican observer put it, ``Donna Arduin is Arnold's John Ashcroft.''

Schwarzenegger himself says Arduin has worked ``tirelessly.''

``I only play the machine in my movies,'' he said before unveiling his budget blueprint in January. ``She is a real machine.''

Arduin does not apologize for the way she is perceived, although she finds it somewhat ironic.

``That's my job. We have a lot of tough fiscal decisions to be made at this time, and my job is to bring those options to the governor,'' she said in an interview. ``I find it amusing that anyone would think that Arnold Schwarzenegger needs his director of finance to be his tough guy.''

Tough stances

But while Schwarzenegger was schmoozing with Democrats and handing out cigars soon after he took office in November, it was Arduin who publicly lectured legislators about their overspending.

In early budget negotiations with Democrats, Arduin insisted on an inflexible spending cap and giving the governor more power to make budget cuts without a vote of the Legislature. That allowed Schwarzenegger to take a more moderate tack later.

``She strengthens Arnold's hand in these meetings,'' said Stephen Moore of the Washington, D.C.-based conservative Club for Growth who has followed Arduin's career -- from Michigan to New York to Florida -- and recommended Arduin to Schwarzenegger. ``She plays a constructive role for Arnold by being the bad cop, so Arnold can be the charming, charismatic and persuasive leader that he is. The two in tandem are a great team.''

Arduin, 40, had a rocky introduction to Sacramento. She stunned Democratic legislators by abruptly walking out of her first appearance before the budget committee. (She was kept waiting for more than an hour, had a sinus infection and was late to a meeting.)

Then Senate President Pro Tem John Burton, D-San Francisco, suggested on national television that Arduin was an ``ogre'' for ending some Medicaid payments for eyeglasses and dental work in her previous job as Florida Gov. Jeb Bush's budget director. For a time, a mock yellow street sign on Arduin's office door warned ``OGRE XING'' -- a joke from Brulte.

Not everyone is amused.

``Her history has been one of slashing and burning on social programs,'' said Assemblywoman Jenny Oropeza, D-Long Beach, the former Assembly Budget Committee chair. ``Her aggressive cutting is not going to play so well here; her policy approach will not prevail.''

Republican Assemblyman Russ Bogh of Yucaipa said, ``The Democrats are trying to demagogue her and intentionally make her feel like she doesn't belong in California.''

Arduin's fiscal conservatism is rooted in her early experience as an intern in President Reagan's Office of Management and Budget under David Stockman.

In high school, she excelled in advanced placement calculus classes. Her father, a basketball and football coach and sports commentator, pushed her to pursue engineering. But Arduin was inspired by a government teacher to study economics and public policy.

After graduating from Duke University, she worked as an analyst for investment banks in New York and Japan before leaving the private sector for government work. She was chief deputy budget director in Michigan and in New York under Gov. George Pataki, before joining Bush in Florida.

Schwarzenegger initially hired Arduin as part of his transition team to conduct an independent, line-by-line audit of the state budget to uncover the ``waste, fraud and abuse'' he promised to find on the campaign trail. She has yet to release a comprehensive report, and the administration now says the audit will be ongoing and phased in over time.

In public appearances, Arduin often comes across as uneasy and slow to smile, even though she was a cheerleader for her Jesuit prep school in Indianapolis. But one-on-one, Arduin's face brightens when she brags about tackling the slopes in Aspen and shows off snapshots of her black Labrador, Clyde, that clutter her desk.

Arduin takes her job seriously, but displays a sense of humor about herself. She has a signed copy of a political cartoon that portrayed her pulling winter hats over the eyes of children -- a reference to her recent proposal to limit or ``cap'' enrollment in a health insurance program for low-income kids.

Attire stands out

In a Capitol where the fashion palette for men and women consists of shades of gray and pinstripes, Arduin also stands out, with her fire-engine-red suit and occasional leather pants and fur collars.

Arduin is uncomfortable in the spotlight, preferring to tout the achievements of her bosses. But when pressed on her philosophy, she explains that government should not unduly burden business.

``People's money either stays in their hands,'' she said, ``or goes to the government. When more money goes to the government, it leads to job erosion.''

Anti-tax groups and libertarian think tanks like the Cato Institute give Arduin high marks for balancing state budgets without tax increases, but Florida Democrats criticize her for moving money around from special funds to pay for tax cuts.

Despite the perception among California Democrats that Arduin is interested only in gutting government, her colleagues say she has pushed for creative approaches, such as looking for ways to overhaul the state's costly Medi-Cal system, instead of eliminating benefits as Democratic Gov. Gray Davis proposed last year.

``She forced us to look deeper and for more thoughtful ways, instead of taking a more ham-handed approach,'' said her chief deputy director, Mike Genest.

At the same time, Arduin is as adamantly anti-tax as Schwarzenegger comes across in public. She has consistently spoken up against any tax increases to balance the budget, when some in the administration have privately pondered the possibility.

Of Arduin, Florida's Senate Democratic Leader Ron Klein said she ``comes from the trickle-down economic theory unabashedly. She's a true believer that the lower you tax people, the less you will impede capitalism and job creation.''