LABOUR'S election campaign was in disarray on Wednesday night after Gordon Brown was forced to apologise to a pensioner and lifelong party supporter whom he had described as “a bigoted woman” for questioning him over the scale of immigration from eastern Europe.

His contemptuous dismissal of Gillian Duffy, made in private but caught by a live broadcast feed, again raises questions about his volatile character and, more importantly, whether the Labour core vote will now be repelled by his apparent indifference to their concerns.

Morale in the Labour campaign slumped as even some of Brown's closest aides vented their fury at him, with one describing him as “a pathetic blame shifter”.

Sensing the damage he had inflicted on his already slim election chances, Brown wrote to party members last night to apologise. “I am under no illusions as to how much scorn some in the media will want to heap upon me in the days ahead. Many of you know me personally. You know I have strengths, as well as weaknesses. We all do,” he said.

Brown had met Duffy, 65, on the streets of Rochdale, in the northwest of England, when she accosted him over a range of issues including the scale of debt, taxes and tuition fees. At one point during the discussion she referred to eastern Europeans “flocking” to Britain.

After an apparently pleasant conclusion to the conversation and closing his car door, Brown turned to his director of strategic communications, Justin Forsyth, declaring the event a “disaster” and demanding to know who was responsible for him meeting Mrs Duffy. He appeared to blame his longstanding aide Sue Nye.

Asked by Forsyth what Duffy had said he replied “Oh everything, she was just a sort of bigoted woman. She said she used to be Labour. I mean it's just ridiculous.”

Brown was then played back his remarks on a live Radio 2 phone-in. He covered his face with his hands, and said he blamed himself. He apologised to Duffy on the phone, and was then going to hold a press conference in Manchester to apologise again, before agreeing to drive back to Rochdale and say sorry to her in person.

He met her in private in her front room, spending 40 minutes at her home before emerging declaring himself the “penitent sinner” and claiming he had been forgiven. The prime minister said “If you like, I'm a penitent sinner. Sometimes you say things you don't mean to say, sometimes you say things by mistake and sometimes you say things you want to correct very quickly. So I wanted to come here and say that I made a mistake but to also to say I understood the concerns she was bringing to me and I simply misunderstood some of the words she used. I made my apology.”

Mrs Duffy was last night refusing to comment or confirm Brown's claim. It was understood that she has sold her story to the London tabloid Sun newspaper. Labour party officials said the prime minister had not realised what she was saying until he read the transcript, and felt frustrated that he was unable to have a proper conversation with her owing to the media scrum around him.

But that also underlines the extent to which he is not a natural campaigner on the stump, an inadequacy likely to be highlighted when Tony Blair briefly joins the campaign in the next few days.

No campaign strategist sought to minimise the damage, amid signs that the Tory vote is anyway starting to harden. The YouGov tracker poll in the Sun showed the Labour vote already starting to slide with the Conservatives on 34 (up one), the Lib Dems on 31 (up three), Labour on 27 (down two) and others on eight (down two).

— The Guardian, London