That, at any rate, is the finding of a YouGov poll published in yesterday’s Telegraph.

Among all voters, 34% chose Margaret Thatcher as the greatest post-war premier; for Lib Dem supporters the total was 27%. She was followed by Harold Wilson and Winston Churchill, with 14% of Lib Dem voters naming them as the greatest post-war PMs. Clement Attlee was highest-rated by 11%. Intriguingly, more Lib Dems chose John Major (albeit just 2%) than did Tories (a rather harsh 0%).

Asked to choose two of Mrs Thatcher’s greatest achievements, Lib Dem voters selected her status as the first female British PM (53%) and her curbing of excessive trade union powers (26%). In third place, with 23%, was what the survey cited as her “keeping Britain in the European Union but more on Britain’s terms”.

Lib Dem voters were more evenly split on Mrs Thatcher’s greatest vices as PM: 44% said introducing the poll tax; 43% reckoned it was her “Undermining the idea of public service and making individual greed seem morally desirable”.

Perhaps most fascinating – if odd – of all was Lib Dem voters’ answer to the question: “If you had to choose and you could pick one of the following at the peak of their powers to be Prime Minister today whom would you choose?” Party supporters appear to be pretty evenly split between an arch-socialist and an arch-capitalist. It would have been interesting to see the results if folk like Roy Jenkins or Paddy Ashdown had been added into the mix. Anyway, here’s how the candidates lined up, in order of popularity:

Tony Benn – 19%
Margaret Thatcher – 18%
Kenneth Clarke – 12%
Tony Blair – 10%
David Cameron – 9%
Gordon Brown – 7%
Don’t know – 24%

Make of it what you will… You can find the full YouGov survey results here.