LONDON, England (AP) -- Britain's bedraggled Prime Minister Gordon Brown walked into a political train wreck yesterday after forgetting to turn off his microphone.

He described a loyal Labour voter as a bigot for asking about immigration, blamed advisers for a "disaster" ahead of next week's election, then rushed back to the voter's house to beg her forgiveness.

All the country could do was look on -- in shock, amazement and sometimes glee -- as the painful, riveting drama played out over television and radio for hours. The debacle created a massive setback for Brown on the eve of the last TV debate ahead of the May 6, vote.Grandmother Gillian Duffy, 66, met with Brown at a campaign stop in the northern town of Rochdale and questioned him about the influx of eastern European immigrants who have come to Britain.

Many people are angry that immigrants are taking jobs at a time when Britain's unemployment level is soaring. More than 1 million eastern Europeans have moved to Britain since the EU gained new members such as Poland, Bulgaria and Romania in 2004, but many have since left during the bruising recession.

Brown brushed the question aside and explained that Britons were also working in eastern Europe, leaving in his car in a hurry and forgetting to turn off his microphone.

"That was a disaster, they should never have put me with that woman. Whose idea was that? It's just ridiculous," Brown is heard saying.

Asked what Duffy had said to upset him, Brown told the aide: "Everything. She's just a sort of bigoted woman."

Duffy, a retired widow who had worked with handicapped children and whose family had all voted for Labour, had questioned Brown on taxes, university fees, immigration and Britain's record deficit of 152.84 billion pounds ($235.9 billion).

Brown's gaffe was immediately broadcast and he was then grilled about it on a televised radio show. Slumped over with his head in his hand, Brown said he realized he had made a mistake and regretted the remarks.

"He's an educated person, why has he come out with words like that?" Duffy said. "He's calling an ordinary woman who's just come up and asked questions ... a bigot."

Duffy said Brown had initially appeared receptive as they discussed policy. "I thought he was understanding but he wasn't, was he?" said Duffy, who said she had planned to vote Labour but would now most likely abstain.

Brown later telephoned Duffy to apologize, then unexpectedly showed up at her home.

Smiling broadly but awkwardly, Brown emerged 40 minutes later and said Duffy had accepted his apology. Duffy stayed in her house and refused to face the cameras.