The landmark decision this week by a state Supreme Court judge in one of the nation’s biggest school-finance cases puts the candidates vying for the mayor’s job in a tight spot. While it is easy for them to say they support more education spending, it is unclear how the city and state would come up with the billions of additional dollars that Justice Leland DeGrasse ordered.

“If the candidates are smart they won’t talk about the ruling, because if they do they will have to present a plan to pay for it,” a political consultant, Hank Sheinkopf, said. “There is no free ride on this one.”

Similarly, the president of political consultancy the Advance Group, Scott Levenson, said: “Everyone is going to punt on the fiscal formulas from the city’s end until the governor comes forward with the state’s share, and because the governor has appealed the decision that won’t happen any time soon.”

The Manhattan judge’s order Monday capped a decade-long legal battle between the state and the Campaign for Fiscal Equity. It directs the state Senate, the Assembly, and Governor Pataki to increase the city schools’ operating budget gradually over the next four years until it has risen by $5.63 billion a year from current levels, and it directs an increase of more than $9 billion over five years in capital spending. New York schools need that much more money – the total exceeds $23 billion – to provide the city’s children with a “sound, basic education,” the court determined.

In many ways, the decision could not have come at a worse time. Both the state and the city are struggling to close multibillion-dollar deficits. Mr. Pataki has suggested the city foot 40% of the bill. Mr. Bloomberg has said the city shouldn’t have to contribute at all, since it is the state that shortchanged the city in the first place.

“The wrongs imposed on the city’s students resulted from the state’s failures,” Mr. Bloomberg said after the ruling. “If new funds are required, the Legislature must make certain that these funds come from all of the state’s taxpayers.”

The state Senate majority leader, Joseph Bruno, has said Albany should not raise taxes to cover the judgment. It is in that context that the mayoral candidates have to tiptoe around the issue.

“Supporting the CFE ruling is easy,” a political consultant, George Arzt, said. “All four Democrats and the may or are going to be united behind it, and then paper over the issue of how to pay for it. First everyone will trumpet the cause of the city, and then say it is the state that has been unfair with its funding and they should bear the costs.”

Neither Mr. Bloomberg, who hailed the Valentine’s Day ruling as a “historic victory,” nor his Democratic rivals are likely to dwell on the impact of possible statewide tax increases on New York City residents, who make up about half the state’s population.

The Democratic front-runner, Fernando Ferrer, who has been a supporter of the Campaign for Fiscal Equity since its earliest days, called the ruling a victory in an interview with The New York Sun yesterday.

“It’s a mistake for Mayor Bloomberg to risk losing billions in precious education funding because he’s unwilling to step up and make sure the city does its part,” the former Bronx borough president said. “The governor’s proposal that the city pay 40% of the cost is ridiculous on its face. Bloomberg’s position that the city pay zero is ridiculous.”

Mr. Ferrer said the money wouldn’t necessarily come from a tax increase. The city could use the proceeds from not-for-profit insurance companies’ going public, he told the Sun.

“It could be we have to bite the bullet and declare an emergency in our public schools. That means we either have to raise taxes or some other adjustments, like the state paying some of the Medicaid payments the city pays now,” he said. “Maybe we should get $1 billion for the West Side air rights. The bottom line is we can’t have an education system no one pays for.”

Mr. Ferrer said he wouldn’t come out with a plan for the city to finance part of the schools judgment because he didn’t want to “give the legislature and the governor any excuse not to come up with the money.” In many ways, he said, the problem is one of the governor’s own making. If he had taken money from the comparatively over-financed districts and put it into New York City, that would have been revenue-neutral, but the Republicans don’t want to do that because it would wipe out their suburban power base, Mr. Ferrer said.

“Now they have to pay the piper,” he said.

One of Mr. Bloomberg’s Republican challengers, Thomas Ognibene, a former City Council minority leader, told the Sun the mayor should stop carping about the money and start pushing his education reform program using the funds the Department of Education has in hand.

Mr. Ognibene plans to unveil a school voucher plan, one that does not require legislative approval, next month. He declined to provide details but said it would start reforming the schools right away instead of waiting for money that might be a long time coming.

“The mayor can hail it, but it is a pyrrhic victory,” Mr. Ognibene said.