Wiktionary
mainstream america
n. that part of American society which is normal, is not deviant because of ethnicity, religion, lack of religion, culture or values
Usage examples of "mainstream america".
In the case of Neal Stephenson, the SF geeks have embraced the author with an obsession unseen in speculative literature since the 1960s, even as his books make barely a blip in the consciousness of mainstream America.
She knew very well about AIDS-one of her friends had died of it long before it hit mainstream America between the eyesand still she did not stop experimenting.
Not long ago I was told that my material was 'too quirky' for mainstream America.
Therefore, your marketing strategies should be directed to economic mainstream America.