Is it funny? Try it out on Mrs Cable

The Lib Dem leader's joke wounded Gordon Brown last week. But it didn't test well at home
His wife, it seems, nearly scuppered the punchline. Vince Cable, the man who lit up the House of Commons last week with his comment that the crisis-dogged Prime Minister had transformed himself from Stalin into Mr Bean, very nearly didn't make the remark at all.

Cable's wife, Rachel, was dismissive of the killer line, which came to the acting leader of the Liberal Democrats while he lay in the bath the evening before he had to meet Gordon Brown across the dispatch box. 'I began thinking about Stalin, and then tried to work out who his opposite might be - someone who is disastrous at everything he tries to control. I came up with Mr Bean.'

However, Rachel, who is a farmer in the New Forest, didn't like it. 'She thought it was rather Punch and Judy and said to me: "Oh no, I don't think so." I always try out my new ideas on her.' Luckily his five staff disagreed and when Cable made his remark last Wednesday, even loyal Labour backbenchers were unable to hide their laughter. The Prime Minister had a face like thunder.

Now a younger generation - visitors to the website Popbitch or viewers of CBBC's Newsround - have become Cable's fans. It is just one of many pithy remarks he has made since taking on the acting leader's role after Sir Menzies Campbell's resignation this summer.

At his office, a rather cramped room off one of the older, Pugin-styled corridors of Westminster, just five staff work on research and administration for him. 'We're a good team,' he says. 'I generate my own material, but they are very important. They tell me when I'm being ridiculous. It's a tough job, because you have to try and think what Gordon Brown and David Cameron will raise during Prime Minister's Questions on Wednesday, and then what is happening during the rest of the week. I don't think people are ever totally spontaneous at PMQs - the best remarks have usually been rehearsed.'

Cable's economic knowledge has enabled him to lead the fray over Northern Rock, the pensions crisis and government borrowing. He described the £24bn bale-out of Northern Rock as the equivalent of 30 Millennium Domes 'without the prospect of a decent rock concert at the end of it'. He also called the Queen's Speech a 'deafening anti-climax'.

'I've begun to realise that you can't use academic language; you have to think in images. So when I was trying to describe the crisis of Northern Rock, I felt that the amount of money that had gone into it, £24bn, wouldn't mean a lot to people because it's so vast, so instead I likened it to 30 Millennium Domes.' Despite the relish with which he delivers his lines, he says: 'I wouldn't say I enjoy Prime Minister's Questions - it's rather like downhill skiing, exhilarating but full of peril because you can crash at any point.'

Although he hurt Brown badly with his Mr Bean jibe, Cable says he likes him. 'He actually has a great sense of humour and is easy to engage with, which isn't always seen. But he knows and I know that my job as leader of an opposition party is to go for the jugular.'

When asked whether he now regrets not standing as a leader, the 64-year-old Twickenham MP replies: 'I did seriously think about it, and I knew I could do it and would do it well, but the general consensus among colleagues was that, because Ming Campbell was almost kicked to death because of his age, they couldn't risk a candidate of the same generation. I just accepted that.'

A former chief economist at Shell, Cable said he was 'semi-literate' at school: 'I couldn't even get punctuation right.' He read natural sciences at Cambridge, then switched to economics. But one clue in his past may point to his theatrical leanings. At 16, he played Macbeth at his school in Yorkshire. 'I was a totally callow, shy youth, but I did enjoy acting, particularly as I fell in love with Lady Macbeth.'

Cable vision

Putdowns that have made Vincent Cable the darling of the Commons:

Victim: Gordon Brown, 28 November, PMQs.

Subject: Labour's secret donations.

'The House has noticed the Prime Minister's remarkable transformation in the past few weeks from Stalin to Mr Bean, creating chaos out of order, rather than order out of chaos.'

Victim: Alistair Darling, 19 November, Commons debate.

Subject:Northern Rock's £24bn bail-out.

'[It is the equivalent of] 30 Millennium Domes without even the prospect of a decent rock concert at the end of it.'

Victim: Alistair Darling, 20 November, Commons debate.

Subject: The loss of two CDs containing 25 million personal records, Britain's worst data protection breach.

'Is it not now the case that the Treasury has replaced the Home Office as the department that is unfit for purpose?'

Victim: Gordon Brown, 6 November, Queen's Speech debate.

Subject: The government's political agenda.

'The Queen's Speech has been long in anticipation, but the sense of anti-climax is deafening. I fear that the Prime Minister now cuts a rather sad figure. He was introduced to us a few months ago by his predecessor as the great clunking fist, but the boxing story has gone completely awry. Like a great boxing champion, as he once was, he has somehow made himself unconscious falling over his own bootlaces and is now staggering around the ring, semi-conscious and lost, and hanging on to the ropes.'

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