Rak-Su have gone to Number 1 on iTunes with their winner's single Dimelo.
Rak-Su were crowned the winners of The X Factor 2017 on Sunday, beating Grace Davies in the final showdown.
The pair were top of the vote at Saturday night's freeze where Kevin Davy White went home, finishing in third place.
Dimelo is Rak-Su's winner's duet, featuring rapper Wyclef Jean and producer Naughty Boy on the group's owns original song.
After Rak-Su were announced the winner, they gave a live performance of the track before its immediate release online to download and stream.
The track is now at Number One on iTunes, and the original version without the featured acts is at Number 4.
Meanwhile, the track has made to Number 6 on the Official Charts so far since Sunday. The full official Top 40 will be revealed on Friday.
If they can go on to the top spot officially they'll be the first X Factor winners to go to Number 1 in three years.
Both Matt Terry in 2016 and Louisa Johnson in 2015 failed to make the top spot.
In addition to their winner's single, I'm Feeling You is at Number 3; Mona Lisa is at Number 5 and Mamacita is at Number 6.
Rak-Su's success with heir original songs comes as they admitted staff advised them to stick to covers.
"The staff were kind of like, 'Okay if that's what you really want to do – it's a risk but fine,'" the winners said on ITV's This Morning today.
They added: "I think for us, it was a case of we knew who we wanted to be and we knew who we were before going on to the show.
"Originally, we just saw it as an opportunity to get some good exposure for ourselves. We didn't know it would go this far."
The X Factor airs on ITV.