Thirteen-year-old twins Lamb and Lynx Gaede are a pop duo who call themselves Prussian Blue.
They are from Bakersfield, California, and have been singing since the age of nine.
Their songs have titles such as Sacrifice, a tribute to Hitler's deputy, Rudolf Hess.
The teenagers make Sieg Heil salutes while singing lyrics like "Strike force! White survival. Strike force! Yeah."
Lynx told ABC News: "We are proud of being white. We want our people to stay white we don't want to just be, you know, a big muddle. We just want to preserve our race."
David Duke, the former Ku Klux Klan leader and presidential candidate, uses their music to attract support.
But critics say the girls have been brainwashed by their mother.
Ted Shaw, the president of the National Association for the Advancement of Coloured People's Legal Defence Fund, said: "It breaks my heart to see those girls spewing out that kind of garbage."
Miss Gaede brought her daughters up on racist beliefs using textbooks from the 1950s.
Prussian Blue, under contract to the white supremacist label Resistance Records, is one of a number of extremist pop bands, such as Blue-Eyed Devils and Angry Aryans.