• Gordon Brown reacts during a radio interview as he is played a recording of himself describing a voter he had just met as a 'bigoted woman'
The slur on Gillian Duffy, a 65-year-old widow and lifelong Labour supporter, in the marginal constituency of Rochdale, came when Gordon Brown was in the privacy of his car and thought the Sky News microphone had been turned off.
The pensioner, who used to work with disabled children and lost her husband to cancer two years ago, had just raised genuine concerns about immigration, the economy and education with the Prime Minister. It was part of a change of strategy to have Mr Brown meet ordinary voters.
The incident – one of the defining moments of the election – played out live on 24-hour news coverage and has had senior figures in the Labour Party privately running up the white flag on the campaign.
Some have said that it has brought home the worst fears they had about Mr Brown's character flaws.
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While Mr Brown apologised and later described himself as "a penitent sinner", many in the party knew that the game was up. One leading Scottish Labour figure bluntly told The Scotsman: "We're f****d".
A Labour MP told The Scotsman: "There is nothing redeeming about this; it was a perfect storm. There is no straw on which we can grasp.
"This woman was perfectly reasonable and was asking a question which concerns many people in a way that wasn't at all bigoted.
"She is the sort of person who is our core voter, and this could have marginalised millions of Labour supporters. Many of them may go elsewhere or stay at home."
Another added: "Those of us who raised doubts about Gordon Brown feel no sense of schadenfreude from this, but it sums up all the qualities which we warned others against.
"His grumpiness, his tendency to blame others, his lack of understanding of people, his inability to cope with people arguing with him and his duplicity of saying one thing to somebody and another when their back is turned."
He went on: "I thought we were just about getting into a position where we would creep back into second place ahead of the Lib Dems. Now I think we look like staying in third and possibly ending up a very poor third."
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Another said: "We can forget about the polls. We will have to see if this has legs, but it could be catastrophic. There could be a meltdown".
A snap poll on Channel 4 news suggested that a quarter of voters would be less likely to vote Labour as a result.
Another senior Labour source described it as "an iconic moment". He compared it to Neil Kinnock shouting, "We're all right!" at the Sheffield rally in 1992, the moment many believe Labour lost that election.
"It was our Sheffield rally moment," the source said.
He added: "Gordon Brown with his head in his hands was a compelling image.
This finally gives a public view of the private Gordon that everyone knew existed, but who has finally outed himself."
He added: "It is inconceivable that Tony Blair would have reacted like that, as he would have realised that immigration is the subterranean issue that is really driving this election, not dismissed the woman's views."
Mrs Duffy had approached the Prime Minister to ask a question on the economy. The six or seven-minute conversation appeared to go well, with Mrs Duffy giving forthright views on a range of subjects.
When they parted, it appeared Mrs Duffy had been won over again. Indeed, she said she would now be voting Labour.
But moments later Mr Brown – who parted with the words it was "good to see you" – then proceeded to attack her when he thought the microphone was off. He turned on an adviser, saying: "That was a disaster. Should never have put me with that, with that woman. Whose idea was that? Sue (Sue Nye, Mr Brown's aide], I think. It's ridiculous."
Then, when asked why it was a disaster, he said: "Ah, everything. She's just a sort of bigoted woman. Said she used to be Labour. I mean it's ridiculous I don't know why…"
Within an hour he was confronted with his words in a BBC Radio 2 interview, which was also broadcast live on television, and showed a haggard and humiliated-looking Prime Minister holding his head in his hands as he listened to the extracts.
Mrs Duffy, meanwhile, had been told of Mr Brown's comments and demanded an apology, stating that she had "liked that Mr Blair", but would "not be voting Labour now".
She added: "He's an educated person, why has he come out with words like that?
"He's supposed to lead this country and he's calling an ordinary woman who's just come up and asked questions what most people would ask him, and he's calling me a bigot?"
The row led to the Prime Minister changing his schedule to give a humiliating apology in a 40-minute meeting in her terraced home. But by then senior figures in the party said the damage was done.
This appeared to be worsened when he emerged from the house alone and grinning, saying that Mrs Duffy had "accepted my apology".
Several minutes later, Labour press officers came out to tell the media that Mrs Duffy would not be saying anything, not even whether she had accepted the apology, and asking journalists, cameramen and television crews camped out at the front of her house to leave her alone.
"This has just made a really bad affair even worse," one senior Labour figure told The Scotsman. "It looks like we are pressuring this poor woman after insulting her. Ultimately, she will have to say something, because the media circus will not go away".
At the door of Mrs Duffy's home, Mr Brown described himself as a "penitent sinner", adding that he was "mortified".
In public, leading figures rushed to his aid. Lord Mandelson said: "All of us sometimes do say things that we simply do not mean and, the moment we have said them, we regret it deeply".
Chancellor Alistair Darling stressed that Mr Brown had apologised for the incident and said the Prime Minister knew "he shouldn't have said it".
Some suggested that it could have been worse because Mr Brown had not sworn or started "stabbing the seat with his pen".
Mr Brown also wrote to apologise to activists, admitting he had let them down.
But his opponents stepped away from an all-out attack.
Lib Dem leader Nick Clegg said Mr Brown had done the right thing to apologise.
The Conservatives, privately overjoyed, said: "Mr Brown's words speak for themselves".
• Gordon Brown speaks to Gillian Duffy before making his gaffe. Picture: PA
WHAT WAS SAID
GD: There's too many people now who, who aren't vulnerable, but they can claim and people who are vulnerable can't get it.
GB: But they shouldn't be doing that. There is no life on the dole for people anymore. If you're unemployed you've got to go back to work.
GD: It's …
GB: You get six months …
GD: … you, you can't say anything about the immigrants because you're saying that you're …
GD: … but all these eastern Europeans what are coming in. Where are they flocking from?
GB: Well a million people come from Europe, but a million British people have gone in to Europe. There's a lot of British people staying in Europe as well."
IN THE CAR
GB: "That was a disaster. Should never have put me with that, with that woman. Whose idea was that? Sue I think. It's ridiculous."
Unidentified Man: "(Indistinct) I'm not sure they'll go with that one?"
GB: "They will go with it."
Unidentified Man: "What did she say?"
GB: "Ah, everything. She's just a sort of bigoted woman. Said she used to be Labour. I mean it's ridiculous..."
Many a slip… and presidents and premiers have all been caught
GORDON Brown will not be the last politician to fall foul of a switched-on microphone in an unguarded moment – and he's certainly not the first.
As his government was falling apart in 1993, Tory prime minister John Major, below, attacked the three "bastards" in his Cabinet who were plotting against him. The radio interview was over when he made the comment, but the tape was still running.
In Scotland, Henry McLeish, while first minister, described then Scottish secretary John Reid as "a patronising bastard" in an unguarded chat with Helen Liddell in a TV studio.
Prince Charles had his moment when he described the gathered media as "these bloody people". Referring to the BBC's royal correspondent, Nicholas Witchell, he added: "I can't bear that man. I mean, he's so awful, he really is."
One of the most famous gaffes was a joke made by the US president Ronald Reagan. In a microphone test, he joked he would start bombing the USSR in the next few minutes.
No list of gaffes is complete without his fellow former president, George W Bush, whose most famous unguarded moment was his "Yo Blair" chat with Tony Blair.
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