The state’s largest hospital associations and health care union are waging a statewide battle against Governor Pataki’s budget vetoes with television, print, and radio advertising campaigns costing millions of dollars.

Responding to Mr. Pataki’s hard-line efforts to slash hundreds of millions of dollars in Medicaid spending that the Legislature restored in its budget, the health care groups shot back this week with a television spot that accuses the governor of getting “everything upside down and backwards.”

A new radio ad suggests that Mr. Pataki’s cuts put lives at risk by depleting the staff of emergency rooms. In newspaper ads and direct mailings, the groups are instructing New Yorkers to swamp the main telephone number of the governor’s chambers with calls of complaint.

The groups say they’ve spent $3.5 million on the campaigns, which is more than the combined fund-raising of all the Republican candidates for governor as reported in the candidates’ January filings.

One of the campaigns is being led by the Healthcare Association of New York State, a statewide lobbying group that represents hospitals and nursing homes. The association and its regional affiliates are spending $500,000 on print ads in 11 newspapers and radio ads on 36 stations in 15 local markets. The powerful health care union 1199/SEIU and the Greater New York Hospital Association are spending $3 million on direct mailings and TV, radio, and print ads.

“We are prepared to spend more if that’s what it takes,” said Brian Conway, a spokesman for the Greater New York Hospital Association, which is coordinating its campaign with the health union.

The campaigns will put to the test the amount of power the groups have over a governor who is stepping down in months and who is trying to polish his fiscal conservative credentials before stepping into the national political arena.

Taking many in Albany by surprise, the governor last week vetoed $2.9 billion in spending and tax breaks and declared most of the cuts constitutionally protected and thus impervious to legislative overrides.

One of the governor’s chief targets was the Medicaid spending – a total of about $1.3 billion in state and federal funds – that lawmakers tacked on to Mr. Pataki’s executive budget.

Mr. Pataki accused lawmakers of overstepping their authority by dismantling Medicaid reforms that he inserted into his executive budget. Hospital associations have threatened to sue Mr. Pataki if he ignores legislative overrides. The Legislature could take legal action against the governor but is more likely to negotiate.

Despite the size and scope of the campaigns against Mr. Pataki, his administration yesterday seemed unfazed. A spokesman for the administration’s budget division said the governor’s cuts to Medicaid were aimed at controlling spending on an entitlement program that has ballooned in recent years.

“Despite the same, tired old scare tactics of the special interests, under the governor’s budget, New York will continue to spend more money than any other state on providing quality health care to its citizens,” a budget division spokesman, John Sweeney, said. “If the special interests want the taxpayers to spend even more than the record amounts they already provide, then the special interests need to say which tax they would raise or what other area of the budget they would cut.”

The governor in his budget proposed increasing total state and federal spending on Medicaid by $100 million, to $45.8 billion, according to estimates provided by the office of the state comptroller, Alan Hevesi.

Officials from the health care groups said there is a different political dynamic at work this year.

It was only four years ago when the president of 1199/SEIU, Dennis Rivera, announced that his union would break party lines and endorse Mr. Pataki’s third-term re-election bid. The endorsement came shortly after Mr. Pataki agreed to give hospital workers a pay raise worth $1.8 billion over three years.

In 2003 – after the union mounted a large advertising campaign – the Legislature overrode more than 100 vetoes, restoring the governor’s Medicaid cuts.

This time around, Mr. Pataki is preparing to retire from office and is considering putting his hat in the ring for the Republican nomination for president. In the past year, he’s taken several trips to Iowa and New Hampshire, far away from the reach of New York’s hospital associations and health union.

“Maybe he feels like he has nothing to lose,” a spokesman for the Healthcare Association of New York State, William Van Slyke, said. “Maybe he feels the best thing he could do is be at war with New York. Who knows? Politically, that might sell in New Hampshire.”

The association has focused attention on Mr. Pataki’s rejection of the Legislature’s attempt to increase emergency room Medicaid reimbursement rates by about 50%.

“The governor is talking about fiscal responsibility,” Mr. Van Slyke, a former deputy health commissioner under Mr. Pataki, said. “I don’t think that 7.2 million New Yorkers who went to the emergency room last year – unfortunately – believe that cutting funding for emergency rooms and hospitals is reform.”

It’s not clear what the Legislature might be willing to give up in talks with Mr. Pataki. The governor could relax his position on his Medicaid vetoes if lawmakers, for example, consent to lifting the cap on the number of charter schools, a high priority for Mr. Pataki.

Senate Republicans are also fighting to keep alive a program that would give property tax rebate checks to homeowners. The governor declared that initiative to be unconstitutional and vetoed it.

Also at play is a possible legislative pay raise. Mr. Pataki has brushed away the idea, but the Democratic speaker of the Assembly, Sheldon Silver, has said he is open to an increase.