For more than three hours members of a Virginia legislative committee sat patiently yesterday, smiles frozen on their faces, listening to Northern Virginia politicians plead for greater representation in the 100-member House of Delegates.

But as the local politicians and some members of the committee that it overseeing reapportionment later acknowledged, the fix may already be in. Powerful legislators from the Norfolk area are poised to repeat what they did 10 years ago when they stripped Fairfax of one of the legislative seats that the Northern Virginians said belong to the fast-growing Washington suburbs.

"My feeling is that Tidewater will win it in committee and the real question is whether Northern Virginia can put it together on the floor [of the House]," said former House majority leader James M. Thomson of Alexandria, who was among almost 30 speakers to urge the Privileges and Elections Committee to raise Northern Virginia's delegation from 19 to 21 members.

Yesterday's hearing at George Mason University marked the latest in a series of confrontations that won't be resolved until the entire General Assembly reconvenes later this month for a special session on reapportionment.

Some area politicians are not optimistic about the prospects. "They've been screwing Northern Virginia for so many years. "It's a mind set," said Del. Elise Heinz (D-Arlington), a member of the House panel who is likely to lose her legislative seat as a result of the changes. "That's one thing the Northern Virginians on the committee are solid on -- that they're not going to shortchange Northern Virginia again."

Del. John Gray, chairman of the committee and a Hampton Democrat, has said that he believes recent population growth in Northern Virginia entitles the area to only 20 delegates, but he was careful to tell reporters yesterday that the committee hasn't yet made a final decision. "We really haven't sat down and talked about it yet," Gray said. "Everybody's got their own idea."

Still, Gray didn't have to issue press releases to tell everyone in the room where he stood. When Del. Gradys Keating (D-Fairfax) produced a map of Fairfax showing 12 delegate seats -- which would boost the area's representation to 21 delegates -- Gray replied with a chuckle: "Let us see the one with 11 on it."

"I dont admit to 11," Keating shot back.

Neither did House Majority Leader Thomas Moss of Norfolk, who still remembers the ruckus that occurred in 1971 when Tidewater legislators argued successfully in court that sailors stationed in Norfolk should be counted as voters. That decision reduced Fairfax's delegate count from 11 to 10.

When Del. Martin Perper (R-Fairfax) noted that increases in defense spending would probably be sending many of those ships out to sea. Moss jumped in. "Mr. Chairman, they're on their way back right now," he said.

All the fuss centers around efforts to insure that state voters are equally represented in the General Assembly and Congress, under the one-man, one-vote doctrine set forth by the courts. Current census figures indicate that Northern Virginia's population of 1.1 million should entitle it to 21 state House seats, under Virginia guidelines that prescribe approximately 53,400 people per seat.

According to a plan drawn up by the Northern Virginia delegation, that formula would mean the allocation of 3 delegates to Arlington, 2 to Alexandria, 3 to Prince William, 1 to Loudoun, and 12 to the two Fairfax County districts that include Fairfax City and Falls Church.

Gray and others have urged that Falls Church be taken out of one of the Fairfax ditricts and aligned instead with the Arlington district, creating a 3-member district of 161,000 that would be demographically perfect but would leave Fairfax County without enough population to quality it for a 12th seat.

Such a plan would benefit Norfolk, which has seen population shifts cut its allowable number of deldgates from 7 to 5 over the past decade. Committee member George Helig (D-Norfolk) said yesterday he was confident that the Tidewater area could squeeze out another seat through a political "marriage" of Norfolk with the Eastern Shore or Chesapeake. "We think we've got enough votes on the committee to keep another seat down in Tidewater," he said.