'It was those hearings which got me into this race, because I was so infuriated,' said Ms Yeakel, while vigorously denying that she was depending solely on sympathy for Anita Hill to defeat Mr Specter. Campaigning in the Republican stronghold of central Pennsylvania last week, she said: 'I never mention Anita Hill now. Only my opponent does.'
Her reason, of course, is that she does not have to. Even in counties expected to vote for Mr Specter, Democrats are having great success in fundraising among Republican women.
The ferocity of the battle between Mr Specter and Ms Yeakel gives an extra twist to the presidential race in Pennsylvania. In 1988 the state voted narrowly by 51 per cent to 48 per cent for George Bush over Michael Dukakis. This year the state is critical to Mr Bush's hopes of staying in the White House. With California almost certain to give its 54 votes in the electoral college to Bill Clinton, Mr Bush has to win three or four of the big industrial states between New Jersey and Illinois. Pennsylvania, with 23 electoral votes, is the most important.
Even without the animosities generated by the Thomas hearings, Pennsylvania politics are peculiarly divisive. James Carville, the Clinton campaign manager, describes the state as having two cosmopolitan centres, Pittsburgh and Philadelphia, separated by an area with the politics of Alabama. In trying to satisfy these different constituencies, local leaders all show signs of political schizophrenia. The Democratic Governor Robert Casey has not even endorsed his own party ticket this year because he is angry about its support for abortion rights.
But it is the zigzag career of Mr Specter, a liberal Democrat turned moderate Republican, that best illustrates the pressures of Pennsylvania politics. He has faced both ways on most questions for 25 years, with the result that almost the only facts not in dispute about him are that he is able, ruthless and extraordinarily devious. A Democrat who knows him well says: 'None of his critics has ever suggested any limitations on his ability. The criticism is that somebody with that ability should do more with it.'
Mr Specter gained national recognition in the Sixties as a junior counsel on the Warren Commission investigating the Kennedy assassination. This early success has come back to haunt him, for he developed the so-called 'single bullet theory'. This was that Lee Harvey Oswald alone must have fired all the bullets that killed Kennedy and wounded Governor John Connally next to him, if several of the wounds were inflicted by a single bullet. The theory, though endorsed by a Congressional inquiry in 1978, is ridiculed by those who believe that Kennedy died at the hands of several gunmen. It was pilloried in Oliver Stone's film, JFK. A local journalist in York, the most Republican of Pennsylvania's 67 counties, said last week that Stone's film would do more damage locally to Mr Specter than his questioning of Anita Hill.
In 1965, however, the publicity surrounding the Warren Commission was the launching pad for Mr Specter's career. Denied the Democratic nomination as district attorney, he turned to the Republicans, dropping his Democratic registration only after he had won the election. Even so, he remained a peculiar sort of Republican. Elected senator in 1980, the year of Ronald Reagan's triumph, he said: 'I didn't come in on Ronald Reagan's coat-tails. I don't feel I owe him anything.' The high point of Mr Specter's opposition to the White House was his vote against Robert Bork as the conservative nominee for the Supreme Court in 1987. According to one source, the White House feared he would also come out against Clarence Thomas last year, 'so when they asked him to interrogate Anita Hill in front of a television audience of 40 million, they calculated on him getting carried away. They thought that, if his ego was involved, they were sure of his vote'.
In the three days that he questioned her, Mr Specter was not only hostile but also seemed to revel in his inquisitorial role. Always disliked in the Senate for his aggression and arrogance, his unpopularity suddenly extended across the nation. Minor eccentricities were widely publicised. When his home was redecorated, senators noticed that his aides refused to let him stay with them.
Lynn Yeakel says she has 'the perfect opponent - absolutely perfect. I have yet to find one person anywhere in the United States who likes Arlen Specter'.
Still, Mr Specter is running level with her, well ahead of Mr Bush in Pennsylvania, where the latest poll shows the President trailing Mr Clinton by 57 to 34 per cent. In York County, where Mr Bush might expect to lead by 20 per cent, he was ahead by only 47 to 40 per cent. If Mr Bush does not pick up enough votes in central Pennsylvania to balance Democratic majorities in Philadelphia and Pittsburgh, he will lose the state.
Watching Ms Yeakel campaign in Harrisburg, the state capital, one can see why she is failing to identify Mr Specter with the Reagan-Bush years. The Anita Hill issue may attract support, but it obscures her other messages. 'Jobs and the economy override everything else in Pennsylvania,' says Celia Fischer, the Clinton campaign director in the state.
Mr Specter emphasises his success in keeping open the Philadelphia naval yard, which employs 47,000 people. His television advertising consists of moving testimony from people he has helped. At town meetings he stresses that he is pro-choice on abortion and has a good human rights record. Ms Yeakel supporters claim the Specter campaign has spread rumours that her family is anti-Semitic and that she belonged to a whites-only country club.
Philadelphia and Pittsburgh were once at the heart of US industry. But in the Eighties the highly paid jobs, which enabled US workers to enjoy a middle- class standard of living, began to disappear. In Pittsburgh, former steel workers who earned dollars 15 ( pounds 7.50) an hour, now earn dollars 7 an hour in non-union jobs. In Philadelphia, 13,500 municipal workers, threatened with the loss of health and other benefits, have voted to strike. Jim Sutton, their union leader, says that the city government's plans would cut by a third his members' dollars 23,000 average annual salary.
Even where the economy is doing better in central Pennsylvania, new jobs do not pay well. One local banker said a packaging firm employing 2,000 people had opened up in his town, 'but they are getting only dollars 6.12 an hour with few benefits'.
Whatever economic plan Mr Bush produces, it will probably be too late to avert massive defections by workers who voted Republican in the past three elections. Mr Specter's best chance of beating Ms Yeakel is to hold on to these votes by stressing what he has done for jobs in Pennsylvania.
Over the past 10 years, Mr Specter's political gyrations make Mr Bush's efforts to conciliate the centre and far right of the party look tame. But his ability to deliver jobs and federal money to his home state means that he stands a better chance than Mr Bush of re- election. According to one Pennsylvania Republican, 'Bush is in real trouble here. He is not going to win Pennsylvania unless something major happens. He's so far removed from real life, he cannot relate to the problems people have here'.