Duffy has both the bestselling single and album of 2008 so far, according to new figures released today.
Statistics published by the Official UK Charts Company show that the Welsh singer's number one hit Mercy has sold more copies than any other in 2008, with Nickelback's Rockstar in second.
And her debut album Rockferry, which just hit the number one spot in the US, is the bestselling album of the year so far, though Coldplay's fourth album Viva La Vida or Death And All His Friends could overtake it, sitting in second place despite only having been on sale for one month.
According to the chart firm, Duffy could become the first artist this year to reach one million album sales with her Bernard Butler-produced debut, which spent five weeks at the top of the album charts.
The bestselling singles of 2008 so far are:
1 Duffy: Mercy
2 Nickleback: Rockstar
3 Basshunter feat DJ Mental Theo: Now You're Gone
4 Estelle feat Kanye West: American Boy
5 Madonna feat Justin Timberlake: 4 Minutes
6 Flo Rida feat T-Pain: Low
7 Sam Sparro: Black And Gold
8 Rihanna: Don't Stop The Music
9 Adele: Chasing Pavements
10 H Two O feat Platinum: What's It Gonna Be
The bestselling albums of 2008 so far are:
1 Duffy: Rockferry
2 Coldplay: Viva La Vida Or Death And All His Friends
3 Nickleback: All The Right Reasons
4 Scouting For Girls: Scouting For Girls
5 Amy Winehouse: Back To Black (Deluxe Edition)
6 Leona Lewis: Spirit
7 Adele: 19
8 Amy MacDonald: This Is The Life
9 Mika: Life In Cartoon Motion
10 Neil Diamond: Home Before Dark