How did Labour know where to aim its cancer-scare mailshot?

Gordon Brown’s latest campaign slogan — ‘Vote Labour or Die of Cancer’ — has a certain apocalyptic vigour about it, don’t you think, even if it was implied rather than directly stated? The party sent out 250,000 ‘postcards’ to women, although they were not the sort of postcards you get when your Aunt Jemima’s been on holiday in Lyme Regis for the week. The gist was: if the Tories get in they’ll stop your chemo, you mug. Or you won’t get treated at all, in time, and you’ll probably die. This caused a small furore — we’ll come to why the furore was a muted furore, rather than a howl of complaint, in time. Most of the people who admitted receiving this missive were outraged, disgusted and so on, and said so. The suggestion seems to be that a good few who received the card would — au contraire, Mr Brown — rather die of cancer than vote Labour, or at least it would be a very close call.