SPRINGFIELD, ILL., JUNE 30 -- An incentive plan to keep the Chicago White Sox from moving to Florida narrowly was approved late tonight in the Illinois General Assembly after a sponsor warned, "We're about to turn the lights out in Comiskey Park."

Final passage came on a 60-55 vote in the House after a tense roll call during which Gov. James R. Thompson worked the House floor in search of votes.

"You bet I was worried," a relieved Thompson told reporters. "Wouldn't you be worried? Weren't you watching the votes? This is a political resurrection from the dead, a baseball resurrection from the dead."

The measure, which could cut $60 million from the team's cost of occupying a new state-funded stadium, earlier cleared the Senate on a 30-26 vote -- the bare majority required for passage.

In a brief Senate debate, bi-partisan backers of the plan argued that losing the team would be a moral and economic blow, and that the incentive plan wouldn't compete for funds with education and other state programs.

"This is the only chance to save the Sox, or tomorrow they're going to be in St. Petersburg," said Sen. Wiliam Marovitz of Chicago.

"It's the last of the ninth," added sponsoring Sen. Timothy Degnan, also of Chicago. "We're about to turn the lights out in Comiskey Park."

"As a native Chicagoan, I'm delighted," Baseball Commissioner Peter Ueberroth said. "This is a great day for the state of Illinois, the people of Chicago and the White Sox. The legislature's approval is a significant demonstration of support for the White Sox and two-team baseball in Chicago."

The team has pledged not to leave Chicago if lawmakers approve the deal. St. Petersburg, Fla., officials have been wooing the team, but White Sox chairman Jerry Reinsdorf said no final agreement had been reached with city officials or those of the Suncoast Dome.

After the vote, the White Sox issued a statement, saying the team was "elated."

"Today's legislative victory is the result of the dedicated efforts of the entire White Sox organization, numerous public officials and loyal Sox fans," the statement said.

On the last scheduled day of the General Assembly's spring session, the plan's fate was entwined with a struggle to draft a state budget without a tax increase. Though funding for the White Sox proposal wasn't tied to higher taxes, many lawmakers said it would be politically impossible to vote for the White Sox while basic state services lack adequate funding.

"What in the name of heaven are we doing!" said Rep. John Dunn of Decatur. "Let's shut this place down and go home and forget the White Sox!"