The phrase "a relatively mainstream" is correct and usable in written English.
It can be used to describe something that is somewhat common or widely accepted, but not entirely so.
Example: "The film received a lot of attention for its unique storytelling, yet it remained a relatively mainstream production."
Alternatives: "somewhat conventional" or "fairly popular".
Mr. Pawlenty is another former two-term governor with a record as a relatively mainstream conservative.
I went with my 51-year-old cousin, Temple, a relatively mainstream psychotherapist.
This is where Brooks drops off from a relatively mainstream (if often wrongheaded) discussion about Egypt's messed-up political institutions and dips into something disgraceful.
She switched gears with the eco-themed thriller Night Moves: a relatively mainstream feature that moved at a faster pace than her preceding work.
During the 2008 campaign, he supported renewal of the federal assault-weapons ban, which expired in 2004, but that's a relatively mainstream position, and he hasn't taken any action to get the ban through Congress.
In a recent interview with the Staten Island Advance, she explained that she planned to start with a relatively "mainstream" menu, with hopes to get a bit bolder as local patrons get more comfortable.
There is an engaged, relatively mainstream population that is thinking seriously about what Iran's experience says about China.
At this point in my life as a parent, I am relatively mainstream in every way except one: my relationship to the digital world.
These bands retained some elements of the orchestral-style arrangements, but they moved away from lyrical mysticism in favor of teen-oriented songs about relationships.Genesis transformed into a successful pop act, and a reformed Yes released the relatively mainstream 90125, which yielded their only US number-one single, "Owner of a Lonely Heart".
Much of what Dr. Chopra, an endocrinologist by training and a former chief of staff at Boston Regional Medical Center, advocates, including meditation and stress reduction, massage, exercise and a healthy diet, has become relatively mainstream.
Despite the graffiti and glazed brickwork, it very much feels like a corporate take on the concept and the relatively mainstream nature of the beer selection - not to mention the staff's somewhat sketchy product knowledge – is not going to turn it into a destination for craft aficionados.
