"mainstream competitors" is correct and can be used in written English.
It can be used to refer to competitors who are part of the dominant or established market in a particular industry or field. This phrase suggests that these are the main or most significant competitors that a company or individual is facing. Example: "Despite facing strong competition from mainstream competitors, our company was able to carve out a niche for itself in the tech industry."
In Assange's view, the donations provide a level of editorial independence that few mainstream competitors have.
The loan sharks portray themselves as ordinary businessmen providing a service where their mainstream competitors fear to tread.
"Kia's quality improvements are far outpacing the industry," he said, "and they are closing the gap" with mainstream competitors.
Of course it helps banks like Charity Bank to differentiate themselves from the more mainstream competitors, but in an ideal world, it would be considered an industry norm.
It is suffering alongside all its mainstream competitors as shoppers switch to online and convenience stores, while the low prices of Lidl and Aldi tempt customers away.
These candidates are generally barred from events like debates and mayoral forums with special interest groups, because sponsors want to give full attention to the mainstream competitors.
Houston Maritime Museum, Aug. 21, 7 p.m., lorensteffy.com WICHITA FALLS Easy Riders The sport of rodeo has gone mainstream, drawing competitors who may not have grown up on a ranch but have the drive to ride livestock for prize money.
Alt-weeklies used to be vibrant and well-respected parts of the media ecosystem; they bred star journalists and covered local controversies that their more mainstream daily competitors were sometimes too timid to address.
Yahoo and Reuters will have other competitors besides mainstream news organizations when it comes to attracting submissions.
That song, a cool finger-snappy anthem, was meant as an indictment of the garish, oversaturated life style advertised by Lorde's competitors on mainstream radio: "Jet planes, islands, tigers on a gold leash / We don't care / We aren't caught up in your love affair".
It wants to claw mainstream users away from competitors with a "complete music service".
