Fewer than 7,000 sales stand between the NHS Choir and frontrunner Justin Bieber in the race to become Christmas Number One.
Bieber's track Love Yourself is ahead of The Lewisham and Greenwich NHS Choir's A Bridge Over You - a mash-up of Coldplay's Fix You and Bridge Over Troubled Water by Simon and Garfunkel - after a weekend with the charity single in pole position.
Just three days remain for the NHS Choir in their fight to beat the pop behemoth after its high-profile TV appearances, leaving the festive top spot too close to call.
Bieber is set to dominate the top three regardless of whether he gets the prime position.
His song Sorry is in third place, while X Factor winner Louisa Johnson will need a Christmas miracle to even reach the top five as Forever Young slipped from sixth to seventh place.
Stormzy's Shut Up is holding firm in the Top 10 after he launched a campaign for Christmas number one, settling at nine in the chart update.
Sales and streams of songs between 12.01am on Friday, December 18 and midnight tomorrow will count towards the 2015 Official Christmas Singles Chart, with the number one announced on Christmas Day. Part of the proceeds from the sale of the NHS Choir's single will go to the Northern Ireland Association for Mental Health charity.