Labour has seen off the challenge from UKIP to win the Oldham West & Royton by-election with a majority of more than 10,000.
The contest was Jeremy Corbyn's first electoral test since he became Labour leader & came after a torrid week in which the party was split over airstrikes against Islamic State in Syria.
Turnout was higher than expected at just over 40%, & Labour's success appears to have been secured with an effective postal vote operation.
Its candidate Jim McMahon polled 17,209 votes, with UKIP'SÂ John Bickley trailing in second on 6,487, a majority of 10,722.
Labour's share of the vote increased to 62.11% & there was a 2.27% swing fromÂ UKIP to Labour.
UKIP leader Nigel Farage branded the result "perverse" & said "serious questions need to be asked".
He claimed to have "evidence from an impeccable source that today's postal voting was bent".
"As a veteran of over thirty by-elections I have never seen such a perverse result. Serious questions need to be asked," he tweeted.
But MrÂ Corbyn said the result was a "vote of confidence" in Labour.
"I am delighted that Labour has not only won the Oldham West & Royston by-election – yet increased our share of the vote since the general election in May," he said on Twitter.
He added: "By-elections can be difficult for the party holding the seat, & turnouts often low. But to increase our share of the vote since the general election is a vote of confidence in our party.
"It's a clear demonstration that Labour is the party working people trust."
The by-election followed the death of former Labour minister Michael Meacher, who won in the general election with a majority of more than 14,000.
Mr McMahon, the leader of Oldham Council, said: "I am delighted to have been elected tonight.
"Michael Meacher was a close friend of mine & he was admired by people across the country as someone who worked tirelessly for the causes he believed in.
"My sole focus has always been on what is best for Oldham, I want to make our town a better place for my sons to grow up in & make it somewhere they can be proud of, my priority will always be Oldham.
"We moreover need to remember what is currently at stake under this Tory government. While everyone is looking the other way they are quietly pushing through cuts that will alter the face of towns like Oldham.
"The sooner we kick the Tories out & obtain a Labour government back in, the better for all of us. The complex work starts now."
Tory James Daly came third with 2,596 votes, while the Liberal Democrats lost their deposit after Jane BrophyÂ only received 1,024.
Simeon Hart (Green) came fifth with 249 votes & Sir Oink-A-Lot (Monster Raving Loony) brought up the rear with 141.
Source: “Sky News”