A fascinating and intense British election campaign is entering its final few days, with Tony Blair raising the spectre of Harold Wilson’s shock defeat by the Conservatives in 1970 to scare wavering Labour voters back into his camp. How damaged has Blair been by the series of leaks over Iraq? What will it do for his support base?

Labour is launching a three-day campaign to run between now and the poll pleading with supporters not to switch to the Liberal Democrats, warning that if just one in 10 of Labour voters in marginals defects in marginal seats, the government will lose.

No-one seems to seriously think the Tories will win – but it seems entirely possible that although Labour will still win, New Labour will be defeated and Blair will go. David Aaronovitch, writing in yesterday’s Observeras its MORI poll gave Labour a fragile three-point lead, had his lines down pat:

The licensed cynicism could have unintended political consequences. We know that the Lynton Crosby strategy has been to suggest that this is all a gigantic by-election in which you can ‘send a message’ to the hated Blair, without actually losing Labour. You can ‘wipe the smile off his face’ without any detrimental consequences.

The Lib Dem version of this is that you may vote Lib Dem anywhere and there’s no danger of the Tories getting in… But the proposition isn’t quite true, as Crosby calculates it isn’t true. A ‘perfect storm’ combination of low Labour and highish Tory turnout, protest voting and differential swing could quite possibly lead to a hung parliament in which the Conservative leader is invited, in the first instance, to try to form a government. If he failed, and if no-one else could step up, Michael Howard would be entitled to call for another poll.

Elections are blunt affairs. For example, if I want to vote for Blair, I actually have to vote for someone – Glenda Jackson in my case – who has called for him to resign. To vote for freedom for Iraq, I have to vote for someone who seems to me to be indifferent to it. And that’s what I’ll do. Because if you try sending messages at elections, it’s quite likely that a message will come back to you. And it’s this: don’t mess about at elections.