It's not cheap having Arnold Schwarzenegger as governor.

For a variety of reasons, not the least of which is his celebrity status as a Hollywood icon, Schwarzenegger's job is boosting state security costs, siphoning cash from political donors and draining dollars from his own wallet.

He's too popular, aides said, to fly on commercial airlines, as predecessor Gov. Gray Davis did, so he uses private jets. So far, he's not sought reimbursement - aides said that may change - and air travel is costing him tens of thousands of dollars.

There's no governor's mansion in Sacramento, and the private house that Davis and the last two governors lived in virtually rent-free is no longer available; the foundation that owns the house has other plans for it.

So when Schwarzenegger's in town, he stays at a suite in the Hyatt Regency across from the Capitol. The negotiated $125-a-night cost is eventually paid by corporate donors like Wal-Mart, Chase Manhattan Bank, Hensel Phelps Construction and other contributors to his 2006 campaign account.

"It adds up," said Marty Wilson, the governor's chief fund-raiser. "We'll spend tens of thousands of dollars at the Hyatt."

The California Highway Patrol, which provides protection for the governor and his family even when he's not doing state business - about a dozen troopers were on his Ohio trip to attend the "Arnold Classic" bodybuilding expo, for example - is spending more on security than it did under Davis.

"He attracts a lot of people and there are extra responsibilities for us as a result," Tom Marshall, the CHP spokesman, said.

Marshall would not comment specifically on security measures, but CHP Commissioner D.O. "Spike" Helmick said more is spent on Schwarzenegger because he's the first governor in quite some time to have young children who also need security.

It's not clear whether Schwarz-enegger's expenses are a net drain on the state treasury, however. He chose not to take the $175,000 yearly salary to which he's entitled.

One Schwarzenegger campaign aide said the wealthy Republican governor has been "hemorrhaging" money from his private bank accounts since taking office in November.

Paul Wachter, Schwarzenegger's longtime financial adviser and close friend, called that assessment an exaggeration. But Wachter said the bills Schwarzenegger has been paying himself are not insignificant.

"He's had to definitely incur expenses out of his own pocket since he's been governor for a variety of things," Wachter said. "By most people's standards, he's spending a huge amount of (his own) money."

The main expense for Schwarzenegger is air travel. Davis used to fly commercial or borrow someone's corporate jet when he had to move around the state. But Schwarzenegger, who gave up flying commercial years ago because he attracted too much attention from fans when he showed up at an airport, uses planes provided by NetJets.

The company, in which Schwarzenegger has a stake, is owned by billionaire Warren Buffet, a good friend.

Depending on the type of plane he uses, an hour trip with six people along can cost Schwarzenegger thousands of dollars, an aide said. When the travel was related to one of his March ballot propositions, Schwarzenegger could bill the entire cost to his "Yes on 57 and 58" committee.

Schwarzenegger can bill the state 50 cents an air mile for himself and aides when he uses his private jet for official governor's business. But he has yet to submit those expenses.

"Because of the budget crisis, the governor is not claiming that," Wilson said. Other aides said, however, that he might start doing so in the future.

When it comes to his Hyatt bills, Schwarzenegger campaign officials asked the state's Fair Political Practices Commission for advice on whether he could charge those to his election campaign.

The committee he used to raise money for the gubernatorial recall election has already been shut down, but a new "Californians for Schwarzenegger 2006" committee was established in January to help pay some of Schwarzenegger's personal expenses and political bills not covered by the state.

The FPPC said he could bill the committee for reasonable hotel costs.

"If Governor Schwarzeneg-ger's temporary lack of a home in Sacramento requires him to travel to Sacramento for one year or less," the FPPC's written response to the 2006 Schwarzenegger committee says, "then payments for his hotel room will be considered to be payments for his travel. ...

"His travel expenses will be limited, however, to those that are neither lavish nor extravagant."

Schwarzenegger can charge the committee for hotel costs for only a year, the FPPC said, because that's all that is allowed under IRS rules for candidate committees.

Jim Knox, executive director of California Common Cause, said he's troubled by donors paying Schwarzenegger's living expenses.

"It's another example of how the system forces elected officials to become beholden to campaign contributors," Knox said. "Our elected officials should be beholden to the taxpayers, not campaign contributors.

"It's also another good reason why there should be a governor's mansion. We shouldn't have campaign contributors pay for living arrangements for the governor. Those should be paid for by the state."

The 2006 committee recently spent $16,000 to buy 1,000 official "Gov. Arnold Schwarzenegger" pens he hands out at bill-signing ceremonies. Schwarzenegger also uses the committee to pay for cigars he hands out to legislators and other visitors to his office.

"We're not out there raising money just for the sport of it," Wilson said. "It's a fairly expensive operation to maintain."