Little Mix are the 11/8 clear favourites to win this year's X-Factor.
have had to take cover at 5/4 after one Swindon punter staked £590 at 12/1 earlier in the competition.
"We are sweating slightly about this punter whose gutsy wager on the (then) freshly formed Little Mix could represent the most astonishing X-Factor gamble of all time," said Hill's spokesman Joe Crilly.
Marcus Collins is the 13/8 second favourite with Betfred and William Hill, ahead of Amelia Lily who is 6/1 with Boylesports.
Misha B is the outsider of five at a general 12/1 and she's no bigger than evens to be the next act eliminated.
Amelia is a general 6/4 chance while the other two acts are quoted at double-figure prices everywhere.