ALBANY — Governor Spitzer took a hit financially and politically in his budget battle against the hospital industry.

Mr. Spitzer spent $3 million of his campaign money and $500,000 of his personal wealth on television ads defending his budget in an effort to counter a well-financed attack campaign waged by the state’s largest health care employees’ union and a major hospital association.

A spokeswoman for the governor, Christine Anderson, said the ad buy depleted the governor’s campaign account, which had stood at $2.9 million in mid-January.

Mr. Spitzer’s ad buy was an unusual tactic for a sitting New York governor and demonstrated his willingness to strike back hard at special interest groups that attack him. It is even less common for a governor to put his personal money behind a policy matter.

A half a million dollars is not small change for the governor. Mr. Spitzer, a son of a wealthy Manhattan real estate developer, is a multimillionaire, but is not in the same league of wealth as Mayor Bloomberg, a billionaire.

The Spitzer administration had hoped the ads would soften the blow landed by the hospital industry, which was spending millions of dollars on television ads, rallies, mailings, canvassing, and lobbying to drive down the governor’s poll numbers and gain support in the Legislature.

One memorable ad by the hospital union and association featured a frail elderly woman saying, “Governor Spitzer, I want you to look at me. And when you cut health care, I want my face to be in front of you. Remember me.”

The administration did not want to follow in the footsteps of Governor Pataki, who responded less forcefully to attack campaigns by the industry and suffered greatly in the polls as a result.

New poll data released yesterday show that despite Mr. Spitzer’s efforts, hospital groups succeeded in draining some of the governor’s popularity among voters. Since mid-February, Mr. Spitzer’s approval rating has fallen to 48% from 61%, according to a new Quinnipiac University poll, which also found that only 31% of New York voters approve of the way Mr. Spitzer is handling health care.

While Mr. Spitzer has insisted that he won’t let poll numbers influence his policy decisions, he has also sought to leverage public opinion in his battles with the Legislature, such as when he has criticized uncooperative legislators during trips to their home districts.

Both Mr. Spitzer and the hospital groups have declared victory in the aftermath of last week’s budget deal. The governor proposed to cut $329.6 million from hospitals in his executive budget but agreed to restore $157.6 million in the final budget, according to figures provided by the governor’s office. Mr. Spitzer also agreed to restore 67.5% of his proposed nursing home cuts.

Despite the restorations, the Medicaid budget is increasing by less than 1%, according to the administration, a significant slowdown in growth caused both by cost-saving measures and cuts in the budget and by the fact that a greater share of Medicaid pharmacy costs are being covered by Medicare.

Spitzer officials insist that the biggest victories will be felt in the long term, including provisions in the budget that redistribute hundreds of millions of dollars to health care providers serving the largest number of Medicaid patients and which allow the governor to overhaul procedure reimbursement rates that have become outdated and fail to reflect actual costs.

Mr. Spitzer has ample time to replenish his campaign coffers before the next gubernatorial election, which is 3 1/2 years away. But Mr. Spitzer will not be able to afford such a large-scale campaign next year in the event of another clash with a special interest group without an aggressive fund-raising effort.

The hospital employees union and the hospital association can better afford to mount another campaign. The union, 1199 SEIU, and the Greater New York Hospital Association, had amassed about $65 million in a political action fund before launching their campaign and used up a fraction of the pot. (The groups spent $4.5 million by the end of February, according to lobby records.)

The governor, however, has made it trickier to raise large sums of cash quickly, announcing when he took office that he was imposing on himself a number of campaign finance restrictions.

He said he would no longer accept individual campaign contributions of more than $10,000, an amount that is less than one-fifth of the state legal limit during an election cycle. He also said that going forward he would not take advantage of loose campaign finance regulations that allow donors to exceed contribution limits by funneling money through multiple LLCs.

Mr. Spitzer spent $33 million in the governor’s race, about 10 times more than his Republican opponent, John Faso.

Mr. Spitzer’s use of his personal money to pay for the ad buy was first reported yesterday by the Daily News’s political blog.