Bookmakers Ladbrokes are currently placing X Factor entrant Amelia Lily as the favourite for Christmas Number One, with odds of 7/2.

Close in second place are Nirvana, at 5/1. A Facebook campaign encouraging fans to buy Smells Like Teen Spirit has more than 850,000 likes.

Other unlikely contenders for the top spot include The Wombles and the cast of TOWIE, who will be releasing a cover of Wham!’s Last Christmas.

Perhaps most frightening of all is the Justin Bieber/ Mariah Carey collaboration on All I Want For Christmas, currently being given odds of 7/1.

William Hill’s spokesman Rupert Adams said: “The X Factor winner no longer looks unbeatable.

“We have seen good money for Nirvana and the cast of The Only Way Is Essex but my money is on Mariah Carey and Justin Bieber.”

Nirvana’s Smells Like Teen Spirit was the band’s biggest hit and is the lead track from their second album, Nevermind.

The story goes that Kurt Cobain came up with the song’s title after Kathleen Hanna, lead singer of Bikini Kill, spray painted “Kurt Smells Like Teen Spirit” on his wall.

Cobain thought the message had a cryptic meaning but, in fact, Hanna meant that he smelled like the deodorant Teen Spirit, which girlfriend wore.