Illinois is trying to wrest from Virginia the right to build a $150 million physics laboratory the state won in a national design contest, triggering an old-fashioned pork-barrel brawl among scientists and their representatives over the prestige, jobs and industries the giant project will attract.

Striking deep into Virginia territory, Sen. Charles H. Percy (R-Ill.) offered to dump his state's second-place proposal and build Virginia's prize winner, as long as it can be done on Illinois turf.

At issue are the National Electron Accelerator Laboratory, the most advanced experimental nuclear physics equipment in the world and the estimated $500 million in local revenues and hundreds of jobs accompanying it.

"I suppose imitation is the highest form of flattery," said Irene Forde-Howard, a spokeswoman for Sen. John W. Warner (R-Va.). "But there is a sense that we are being usurped . . . . I suppose if it weren't so serious there would be comical aspects to this."

Virginia has countered by sweetening its offer: dangling more professorships, more housing, more money to attract the laboratory.

The fight began in April, when two scientific groups empaneled by the Department of Energy and the National Science Foundation selected the proposal of the Southeastern Universities Research Association (SURA) after a national search. The facility would be located in Newport News, Va.

SURA is a consortium of 23 universities including Catholic, Georgetown, George Washington, George Mason and American universities, the University of Maryland, the University of Virginia, Virginia Tech, Georgia Tech and Duke.

The SURA machine, designed by James S. McCarthy, a physicist at the University of Virginia, was picked on the basis of its scientific merit, since it could accelerate elementary particles to higher energy levels than other proposals and allow for later add-ons of equipment to conduct new experiments, while still using the simplest technology.

But as soon as the scientific panels had spoken, those backing the second-place proposal, one from Argonne National Laboratory in Lemont, Ill., cried foul. Percy called the White House to protest. He met with Energy Secretary Donald P. Hodel, whose department is funding the project along with the National Science Foundation. He and Rep. John N. Erlenborn (R-Ill.) organized troops of Illinois businessmen, six midwestern governors, a dozen universities and assorted scientists to press the matter.

They complained that Virginia had unduly influenced the panel by offering sweeteners like buildings and land worth $12 million and the promise of 35 new faculty positions in nuclear physics--a stunning number that would expand the sub-field of American nuclear physics by 10 percent.

Midwestern universities would be able to offer professorships if they were given a chance, Percy aide Howard S. Marks said. In addition, the Illinois delegation argues, putting the lab in Virginia would create a new national laboratory, something this administration has fought.

Besides, Marks said, Virginia ranks second in the nation in per capita federal expenditures while Illinois ranks 46th. "This is a classic Sunbelt versus Frostbelt issue in which more and more money is drained away from the Frostbelt," he said.

Though Sens. Warner and Paul S. Trible Jr. (R-Va.) and Rep. Herbert H. Bateman (R-Va.) for some years have been quietly lobbying for the SURA proposal as it was being planned, the campaign went into high gear when Percy began to lobby for the Argonne National Laboratory.

With Percy lobbying the White House, the Virginians enlisted the president's science adviser, George A. Keyworth, who wrote to Rep. Bateman:

"The clear intent of this amendment to cut off money for the project is to use the political process to determine priority for scientific projects . . . . It would weaken the framework upon which American scientific preeminence is built . . . . It clearly places local self-interest above national objectives . . . ."

Bateman has also showered his congressional colleagues with more than 100 "Dear colleague" letters and lobbied on the House floor and by telephone. Warner and Trible have arranged a group session in which officials from nine states will lobby Hodel.

"It was a fair competition," said Dan Beck, a Bateman spokesman. "The SURA proposal was picked fairly by a group of scientists as the best proposal. It should win, unless they change the rules of the game."