I was saying last night that we had yet to have our ‘Joe the plumber’ moment in the campaign. We had not even had the Sharon Storer moment, though David Cameron’s encounter with the father of a disabled child had its moments.

Now enter the campaign Gillian Duffy.

It is of course manna from heaven for the media. A new character. An encounter that will be played again and again on TV, not just in Britain but around the world. And something which absorbs all the space in the debate that Labour had been hoping might move to policy, and moves the focus to questions of character.

Question marks about the ethics of Sky notwithstnding (in my day there was an agreement that the mikes were only live when cameras were running) I am not blaming the media for this. And nor is Gordon.

I saw him at his Manchester hotel, where we are preparing for tomorrow’s debate, when he returned from Rochdale. To say he was mortified is an understatement. I don’t think I have ever seen him so angry with himself. And he was angry less about the obvious frenzy he had unleashed than the fact that he said what he did. She was so clearly not a bigot, and he knew that.

There were some members of his team worried about him going to see Mrs Duffy face to face – he had already apologised on the telephone – because of how the media might interpret it and what she might say afterwards.

But he was determined to see her, because he knew he had hurt her, and wanted to attone for that, however humiliated others would say it made him.

I just heard a PR adviser, Phil Hall, saying he felt it was a bad thing for him to go to see her, that he had apologised and he should have moved on. He then gave all the pros and cons. But it overlooks the fact that in the end GB was reacting less as a calculating politician than a human being who knew he had done something wrong. GB felt a very human need, for himself and for Mrs Duffy, to go to see her. It really was as simple as that.

He knows millions of words will be devoted to this – they already have been. He also knew that until he went to see her, he would have nothing else on his mind at a time when the central choice in this campaign – the economy – is about to move centre stage.

It was a mistake. He knows that. But he also knows there is an election to fight, and hopefully he will be back in the hotel soon ready to resume that fight against a Tory Party that would damage the lives of people who live in places like Rochdale.

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