Until recently, the number of season four Idols to hit the charts has been somewhat small compared to other seasons. With his debut at No. 75 on the Billboard 200 for his self-titled debut album, Constantine Maroulis has changed that. What's even more impressive is that he achieved this while releasing the album under his own independent label, Sixth Place Records.

As far as the "Idol" seasons go, season five has seen the most success on the charts thus far. Eight of the season five contestants have already charted. Here is an updated breakdown of charted singers season by season:

*Season one: (five)
Kelly Clarkson
Justin Guarini
Tamyra Gray
R.J. Helton
Jim Verraros
*Season two: (four)
Ruben Studdard
Clay Aiken
Kimberley Locke
Josh Gracin
*Season three: (seven)
Fantasia
Diana DeGarmo
Jasmine Trias
LaToya London
George Huff
John Stevens
Jennifer Hudson
*Season four: (four)
Carrie Underwood
Bo Bice
Constantine Maroulis
Mario Vazquez
*Season five: (eight)
Taylor Hicks
Katharine McPhee
Elliot Yamin
Chris Daughtry
Paris Bennett
Kellie Pickler
Bucky Covington
Mandisa
*Season six: (two)
Jordin Sparks
Blake Lewis
*Non-finalist William Hung brings the total to 31.