George Galloway's shock victory in Bradford West has cost bookies hundreds of thousands of pounds in the biggest ever by-election payout in history.
Ladbrokes said punters were walking away with up to £100,000 after the new Respect MP beat odds of up 33/1.
Mr Galloway ripped up the form book as the Labour candidate went down to a heavy loss - despite being quoted as the heavy 1/50 favourite by the firm at the outset of the campaign.
Alex Donohue, of Ladbrokes, said: "Galloway has hit us for six. His supporters have pulled off a political gamble of epic proportions.
"We naively assumed the money at big prices was an attempt to slash the odds for the campaign. We couldn't have been more wrong."
Mr Galloway's odds were brought in over the course of the campaign, rating 20/1, 10/1 and then 5/1. Betting was briefly suspended as money piled on the Respect campaign.
Ladbrokes said it was not offering "specials" on Mr Galloway - including 25/1 he does a cat impression as the Bradford West MP in Parliament, a reference to his appearance on Celebrity Big Brother in 2006.