The housemates, alongside Darryn Lyons, Bobby Sabel, Kerry Katona and Lucien Laviscount, are all competing to win Channel 5's first series of the programme.
Irish twins Jedward, who have been heavily backed to triumph throughout, are currently 8/13 favourites. William Hill claims that their success could cost it over £20,000. The bookmaker also revealed that it is growing "increasingly nervous" about Paddy Doherty and Amy Childs's chances of winning on Thursday.
"Amy was well-backed at the start of the show, but given the fact that she spends more time looking in the mirror than actually engaging with the other housemates, we are not too worried about her winning," a spokesman said. "Paddy and Jedward, on the other hand, have us very nervous at the moment. Both look like they could win the show and both could cost us a fair amount by doing so."
However, Kerry Katona sits behind Jedward as second favourite, with odds of 2/1. My Big Fat Gypsy Wedding star Doherty is third at 13/2.
The spokesman added: "We have been in fear of Jedward twice before - when they were heavily backed to win both The X Factor and Eurovision, and neither of those gambles came to fruition; however, there is a strong feeling that the Grimes lads can make it third time lucky and give us a real 'Jedwarding'."
Celebrity Big Brother continues tonight at 10pm on Channel 5.
> Celebrity Big Brother: Lucien Laviscount mother backs Kerry Katona relationship
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Watch the latest footage from the house, as Paddy and Lucien react to Kerry's honest discussion: