This is no mean achievement. At her campaign HQ in the Ebbw Vale Conservative Club she can now enter the men-only area. The wall that separated Men's and Mixed bars in the building is long gone, but an invisible threshold, where the wall once stood, remains. Other women still do not pass the dividing line. But, as she puts it, she has been granted honorary maleness, thus enabling her to meet male voters, a necessity in an area where Tories are so few on the ground they might better be found by David Attenborough.
But for all her success in breaching Conservative Club barriers, Blaenau Gwent still looks like a mission impossible. The 298th target seat for the Tories, the Labour vote was 34,333 at the last general election in 1992, compared with the Tories who finished in second place with 4,266. In towns like Ebbw Vale and Tredegar to find one Conservative is an achievement, and to find two is worth a documentary.
Miss Williams, 32, is an unusual candidate for such a seat. Not only is she a high-flying investment strategist, she is a former Tory councillor from the London borough of Wandsworth - once Lady Thatcher's favourite council - and the first woman to be selected by the Tories in Blaenau Gwent.
Nor is she likely to be fazed by the patriarchal attitudes to be found in the working men's clubs of the valleys. She is a member of the 300 Group, formed to get more women into Parliament, and retorts at questions about her selection: "I was selected on my merits, not on my chromosomes."
It will take all her merits to convince the people of Blaenau Gwent to vote for her. It remains as socialist as it was in the days of its former MPs, Michael Foot and Aneurin Bevan, the predecessors of the present incumbent Llew Smith.
But the traditional industries which once dominated the valleys are gone. No deep pits remain; the steel industry has been reduced drastically; male unemployment is high and wages are low; long-term disability is at record levels and property prices are depressed.
The Wales Miss Williams knew could not have been more different, even though it is but a few miles away. "My family used to spend holidays here and then I used to come down at weekends. I had a friend in Hereford and we would meet in Brecon and go horse-riding. Then about eight years ago I bought a house in Brecon. It wasn't one of those weekend cottage jobs - my idea was that eventually I would move down," she explained.
"But I didn't realise what I had done. It needed a new roof, new walls, floors, stairs, electricity, plumbing, everything. I wanted to do it up, but then I became a councillor in Wandsworth and you just don't have the time."
Her claim to Welshness is through her husband Hugh whose father was born in Tredegar. She says she is keen to start the campaign and rejects the idea of it being a mission impossible.
"Things are changing here. The houses are nice, windows are double-glazed, and it is very hard to find an area that looks awful. On the council estates a lot of houses have been bought. Attitudes are changing.
"I think a lot of people are influenced by how their parents voted, but more people from the valleys are going to university which gives people a wider horizon and a willingness to question things."
But surely things cannot change that much between now and 1 May. And isn't this a dress rehearsal for the next campaign in a more winnable seat? (Jonathan Evans, who fought Blaenau Gwent, won neighbouring Brecon and is now junior minister at the Welsh Office.)
"When I was selected here I said I would give it my best shot. I am going to fight the seat to win and I'm not going through the motions before fighting a 'proper seat' later. And on 2 May I will be celebrating."Reuse content