The Hillsborough charity single, He Ain't Heavy He's My Brother, is this year's Christmas number one.
Released under the name The Justice Collective, it features names such as Robbie Williams and Sir Paul McCartney.
It is raising money for the families of 96 Liverpool fans who died in a crush at Hillsborough stadium in 1989.
A cover of The Hollies' 1969 hit, it sold 269,000 copies, 45,000 more than X Factor winner James Arthur's single Impossible which dropped to number two.
Arthur, who had been ahead in the race earlier in the week according to the Official Charts Company, now has total sales of 749,000, making him the most successful X Factor winner since Alexandra Burke in 2008.
Liverpool Walton Labour MP Steve Rotheram, who backed the Hillsborough campaign, said: "We have done in nine weeks what it normally takes nine months or more to achieve, working with a phenomenally dedicated team all of whom have worked for free."
Music retailer HMV said demand for the record had been "absolutely huge" in Liverpool.
Its Liverpool branch initially ordered 12,000 copies of the CD but had to restock in the middle of the week after selling out.
Many customers bought multiple copies, including one man in his 20s, who bought 96 copies - one for each of the supporters who died in the tragedy.
"We haven't seen anything like that since Band Aid," said HMV spokesman Gennaro Castaldo.
Although demand for the single was not as high around the rest of the UK, Castaldo said "it was still clearly substantial, and it would have needed to be for the song to overtake an X Factor single".
Unusually, both the Hillsborough single and the X Factor song were available on CD - increasingly a rarity in an era when downloads account for 99% of all single sales.
The rest of the festive top five was filled by American artists - although Britney Spears does attempt a British accent in her duet with Will.i.am, Scream And Shout, which was at number three.
Rihanna's Stay was at four, while Bruno Mars's Locked Out Of Heaven was this week's number five.
Several classic Christmas songs made their annual reappearance lower down in the top 40, led by The Pogues' Fairytale Of New York at number 12.
Other seasonal hits included Mariah Carey's All I Want For Christmas Is You, Wham's Last Christmas and Wizzard's I Wish It Could Be Christmas Every Day.
Unsigned artist Alex Day, who has a cult following on YouTube, managed to get his festive single Stupid Stupid to number 25.
This was something of a comedown for the Essex musician who reached number four in last year's Christmas chart, beating Coldplay in the busiest week of the year for record sales.
Another novelty hit in this year's top 40 came courtesy of Shahid Nazir, now perhaps better known as "One Pound Fish Man" after his market stall jingle became a viral hit on YouTube.
His song, cunningly titled One Pound Fish, was at number 29.
In the album chart, Emeli Sande took the Christmas top spot with her debut record Our Version Of Events.
Featuring the singles Heaven, Next To Me and Read All About It - which Sande performed at the Olympic Closing Ceremony - it is the UK's biggest-selling album of 2012, shifting 1.32 million copies since it was released in February.
The rest of the top five featured Olly Murs, Michael Buble, Bruno Mars and Neil Diamond.
See the Christmas 2012 number one video below: