William Hill make Tom their the red-hot favourite at 8/11 to be the first housemate evicted this Friday night when the winner of Big Brother will be crowned.
Louise is the 6/4 second favourite.
Alex has been cut for victory from 4/6 to 4/7 while Aaron is 3/1.
“This year’s Big Brother has been one of the closest ever and it has only been in the last week or so that Alex has really stretched her lead,” said Hill’s spokesman Joe Crilly.
“It would appear that second place is between Aaron and Jay while Tom and Louise don’t appear to have any realistic hope of winning.”