The song has come from nowhere to be one of the hot festive faves.
Gordon says he wrote the song at home and finished it in a branch of Safeway while he was waiting for his mum to finish her shopping.
Huge sales
More than 150,000 people have ordered copies of the single, which is about double the number of sales needed to go to number one.
The Tweenies, Sophie Ellis Bextor and Cliff Richard are some way behind in the top slot stakes but with a Christmas number one you never know!
S Club 7 are still your favourites in our Christmas number one vote. Click on the link at the top right of the page and get voting!
Hear story
Watch Becky Jago's report
Vote: who should be Xmas number one?
