Labour has stormed to victory in the Oldham West and Royton by-election, in a massive boost for beleaguered party leader Jeremy Corbyn.
Jim McMahon, the local council leader, won 17,209 votes – pushing UKIP's John Bickley into a distant second place with 6,487 votes.
UKIP had not been confident of unseating Labour, but had hoped to slash the 14,738 majority won by the late Michael Meacher in May's general election. In the end, however, the majority remained high at 10,722 votes.
A lower turnout of 40% in this by-election means Labour's majority has actually increased from 34.2% to 39%.
UKIP leader Nigel Farage immediately warned of foul play, tweeting that he had "evidence from an impeccable source that today's postal voting was bent". UKIP's deputy leader, Paul Nuttall, told journalists the "postal vote has distorted the result", saying: "You've got to ask yourself, is this Britain or is this Harare?"
But McMahon dismissed his claims, telling the BBC: "UKIP just need to understand that people have the right to vote for the party that best represents their interests.I can say with confidence that we represent every community in Oldham – and every community came out and voted Labour."
Hours earlier Farage had admitted that postal votes would probably swing it for Labour thanks to a "particular block vote that is a very difficult demographic for UKIP". Bickley told BuzzFeed News on Tuesday that Labour was "very strong in the Muslim community".
In a statement, Corbyn said: "I am delighted that Labour has not only won the Oldham West and Royton by-election – but increased our share of the vote since the general election in May.
"Jim McMahon will make an excellent MP and a worthy successor to Michael Meacher, and I am looking forward to welcoming him to Labour's team at Westminster. Jim ran a great campaign, focusing on bringing jobs to Oldham and giving every child the best opportunities."
Corbyn said the result was "a clear demonstration that Labour is the party working people trust", adding: "Our determination to oppose Tory austerity policies and our successes in pushing them back on tax credit and police cuts show that Labour is getting results for working people."
McMahon said: "I am delighted to have been elected tonight. Michael Meacher was a close friend of mine and he was admired by people across the country as someone who worked tirelessly for the causes he believed in. I will do my best to live up to those high standards."
Here are the full results.
Jim McMahon (Labour): 17,209 (62% of vote)
John Bickley (UKIP): 6,487 (23%)
James Daly (Conservative): 2,596 (9%)
Jane Brophy (Liberal Democrat): 1,024 (3.7%)
Simeon Hart (Green): 249 (0.9%)
Sir Oink-A-Lot (Monster Raving Loony): 141 (0.5%)
The by-election win is a major boost to Corbyn after a torrid few weeks in Westminster. But some campaigners said it was McMahon that deserved full credit – and that Corbyn was often a hard sell on the doorstep.
Richard Angell, chair of centrist Labour think-tank Progress, told BuzzFeed News: "Today's result is all Jim, Jim, Jim.
"When national issues looked like they might take their toll on the campaign, a council leader with real results, huge local support, and a stronger brand than Labour has delivered a great result for the party. This victory is all Jim's."