Stephen Pollard: The write stuff: a tale of obsession in the political jungle

'I'm not sure how I feel about having imaginary chats with Mr Blunkett in Sainsbury's'

When I told a friend that I was about to start writing David Blunkett's biography, he asked me if I had a spare room. I looked puzzled. "The best piece of advice I ever received," he said (he is in the middle of writing a biography himself) "was that it would feel as if your subject has moved in with you. And when you go to the supermarket, he'll be queuing with you."

I can't say how accurate that advice will turn out to be, since I have only just begun what will be a near three-year project, but I'm not sure how I feel about having imaginary chats with the Home Secretary as I rummage through the vegetables in Sainsbury's.

It's a pretty daunting prospect. I've never written a biography before and, as everyone to whom I have spoken about the topic tells me, the only way to find out how to do it is to start. However, more than that – and I suppose that every biographer feels the same about his or her subject, or else they wouldn't be doing it – there's simply so much ground to cover: a full career in local government in Sheffield, the opposition years in Westminster, his time as a pivotal figure in the battles to make Labour sensible again, and now government.

And then there's the extra-curricular side of the man: what makes him tick, how has his blindness affected him? And how do I get all that into 150,000 words?

I have a voracious appetite for biographies, and political biographies in particular. I don't recommend it as an obsession. Unless you have endured the sheer tedium of Sir Norman Fowler's Ministers Decide (which, at least, deserves immortality for its fabulously dull title), you can't begin to understand the nature of boredom. On the other hand, The Independent happens to employ the authors of the two finest books to have been written about New Labour – Donald Macintyre's Mandelson, which changed my entire perspective on politics, and John Rentoul's Tony Blair: Prime Minister, which fully deserves the word authoritative.

Back-scratching over. Both books are doorstoppers, and that's been a new trend in recent years. There has always been a market for the extended Sunday supplement biography, not meant as a final word but designed to provide some context in the middle of a career. Robert Harris's early book about Neil Kinnock was the archetype.

Of the current generation of politicians, there have been books like that about everyone from Gordon Brown and Robin Cook to William Hague and Ann Widdecombe. However, both the Macintyre and the Rentoul books are proper extended biographies, offering an overview and a sense of perspective, which in the past would have come out only at the end of a career. Macintyre wasn't to know that his subject's political career would be over so soon.

Political biographies today – the same is true of autobiographies – are only considered a success if they contain a revelation or two, and the bigger the better. And that's where the money lies – in newspaper serialisations. My editor has also edited Mo Mowlam's forthcoming memoirs. When I asked him where they were being serialised, he made it clear that this was a very stupid question: "I can't tell you that; we have to keep it secret in case of spoilers." There's big money, and big news, involved in these things.

In that context, Paul Routledge's biography of Mandelson was as good as it gets. Routledge detailed Mandelson's home loan and forced his resignation. I should declare an interest here. Routledge is also working on a biography of David Blunkett. As one report of our forthcoming battle of the biographies put it: "Bruiser versus pointy-head." (I like to think I am the pointy-head, but anyone who has seen me in the gym may have a different view.)

Although my book will not be authorised – the Home Secretary will not be able to veto anything that I write – I am enjoying his full co-operation. Routledge is not, and I suspect the tone of his book can be judged from his working title: Blind Ambition. I wish him good luck. I'd rather be in a crowded market than an empty one.

Last week I discovered a hidden club, to which I had no idea that I belonged. I mentioned to someone that William Hague had chosen, as his Desert Island book, Robert A Caro's Means of Ascent, the story of Lyndon Johnson's 1948 Senate victory. I was thrown by this, as I had never before come across anyone else who shared my view of the book as the finest piece of biography ever written. "Me too," my companion said. And then he told me about three other people who would also make Means of Ascent their Desert Island choice.

Well, it might be that we are the six weirdest people on the planet. Or it might be that, if you're fascinated by politics and enjoy biographies, you should log on to Amazon now and buy it. And what's more, the latest volume of Caro's life of LBJ is out in April. I am, literally, counting the days.

stephenipollard@hotmail.com