As staffers dismantled her campaign headquarters yesterday, Virginia state Sen. Jane H. Woods reflected philosophically on a political career that she acknowledged now could be over after her paper-thin loss Tuesday to Democrat Leslie L. Byrne.

The defeat of Woods, 53, a former schoolteacher, shocked her fellow Northern Virginia Republicans, who were otherwise jubilant over their party's history-making capture of both houses of the General Assembly. Byrne, 52, a former Virginia delegate and member of Congress, emerged victorious in unofficial returns by just 36 votes out of more than 30,000 cast in a three-way race.

"I've had really big battles," Woods said yesterday in her Fairfax City office. "You learn they happen for a reason, and the outcome is for a reason. But another door opens. Always."

Referring to a bout with cancer several years ago, she said, "You don't lie in a hospital being told you have six months, and get through that, and ever again see a fall as insurmountable."

But, should her defeat be confirmed in a recount considered all but inevitable, Woods said she would be disinclined to run again after spending four years in the House and eight in the Senate.

"You never say never, but probably," she said when asked if this is her political swan song.

Her campaign is waiting for official returns from the state before deciding whether to ask for a recount. Woods said a recount is "virtually automatic" when the margin of victory is so thin. A conservative third-party candidate received 9 percent of the vote, draining support from Woods, her supporters believe.

In addition, Woods said yesterday she had heard from several voters who said that when they went to vote Tuesday, they were told they were not registered.

State and county election officials estimate that thousands of people statewide were turned away from the polls even though they thought they had registered to vote at Department of Motor Vehicles offices. The 1996 "motor-voter" law was intended to make registration easier, but officials said there have been some glitches.

"People didn't get to vote because the applications didn't reach us," said Robert W. Beers, Fairfax County's general registrar. "They're furious, but there's nothing I can do about it."

Woods attributed her loss primarily to "a very effective effort by social conservatives" backing independent candidate Virginia T. Dobey, 44. "They were able, through some very sad misinformation, to scare people," Woods said, referring to charges that she promoted euthanasia by supporting a law that expands participation by non-family members in decisions about resuscitation.

Byrne said Dobey took votes from her tally as well. "Obviously I think Woods lost more than I did, but I don't think it was all a one-way street," Byrne said.

Woods said she could not help but feel sad after an eight-month campaign. "I'm disappointed for the hundreds of people who pitched in and gave their hearts," she said.

Although the GOP was able to hold its slim margin in the Senate and capture a slender majority in the House, its relatively poor showing in Northern Virginia is cause for alarm, Woods said.

"The Republican Party scares people inside the Beltway," she said. "It should be a very loud wake-up call."

CAPTION: Sen. Jane H. Woods (R-Fairfax) and Rep. Thomas M. Davis III (R-Va.) greet a voter Tuesday. Pending a recount, Woods's political career may be over.