Fairfax County Supervisor Audrey Moore said yesterday that she inadvertently voted against a 1979 motion to build the Dulles Toll Road, reversing a statement last week that said the record showed she supported the heavily traveled road.

Moore, a Democrat representing the Annandale District, is challenging Republican Board Chairman John F. Herrity in the Nov. 3 election. Her voting record on the toll road has been a campaign issue since last week when Herrity called her a "flip-flop artist," saying she only sometimes supported the road.

"I think that Mrs. Moore's campaign should apologize to me and the public for the misleading statements," Herrity said. "It points up that Mrs. Moore has voted against almost every significant transportation improvement with countywide implications."

The dispute over an eight-year-old vote -- only one of many that board members cast on the Dulles Toll Road -- reflects the importance both candidates attach to establishing an image of having improved the transportation system. Polls have shown repeatedly that a large majority of residents say traffic is Northern Virginia's leading problem.

Moore denied Herrity's allegations that she has tried to block major road projects and continued to say she supported the toll road. Last week, she called for a special referendum next spring on whether to approve the sale of $100 million to $150 million in bonds to pay for road and rail improvements.

Moore revised her previous statements on the toll road after a reporter told her that a tape of the meeting, ordered from the county archives, showed Moore cast the only "nay" vote against the major arterial on July 9, 1979.

"It was just a simple mistake. I've always supported {the toll road}," except for the vote that sought $5 million in county funds, she said.

After reading a summary of the 1979 meeting, Moore said she had inadvertently confused two motions on the toll road, voting against her intention on each of them.

According to the tape, her first vote supported the use of car pools on the Dulles Access Road, something she said "I am on record against." Her second vote opposed the construction of the toll road, which runs parallel to the airport access road. She said on several other occasions she is on record supporting the Dulles Toll Road.

Herrity said the more important vote on road was the $5 million appropriation that Moore opposed in 1982. "It's sort of ridiculous to say you're in favor of something if you're not willing to pay for it," he said.

As for the 1979 vote, the Republican said: "How many different explanations have we had in the past few days? Four? How many more times is she going to explain her record?"