By 1983, even in the US "pure" synthpop was incredibly successful in the mainstream arena, as evidenced by the #1 performance of Michael Sembello's "Maniac," thrust to the top of the charts after appearing on the soundtrack for the hit movie Flashdance. The Giorgio Moroder helmed and Irene Cara performed song "Flashdance… What a Feeling" did so as well. For that matter, everything about the movie Flashdance was a big surprise hit in 1983.
Sembello's song, although popularized by the movie, actually wasn't written for it, and was originally penned after Sembello was inspired by seeing the grindhouse 1980 splatter flick Maniac about a serial killer in New York who scalped his victims and made mannequins decorated with their hair. The lyrics were even changed; the maniac in the original version was male, not female, and rather than dancin' like he's never danced before, he would kill your cat and nail it to the door.
Whatever inspired Michael Sembello to write a disco/synthpop song about a serial killer is unclear, but luckily for him, he was convinced to update it to something a bit more accessible, and he hit mainstream gold with this tune.
That gets a bit into the question of exactly what the profile of the synthpop fan was in the 80s, but that's more fairly the topic for another post and another song. For now, let me just say that with the kind of mainstream success songs like "Maniac" was having, Human League's "Don't You Want Me Baby," pretty much the entire early to mid 80s catalog of Duran Duran, and much more, clearly shows that this kind of music didn't have just niche appeal.
Michael Sembello quietly disappeared after this song, and is known today as a one-hit wonder who swept in with one gigantic hit and then was completely forgotten. He also "wins" for being one of the least image conscious synthpop stars; as a sweaty, hairy bearded guy in a black tank top, he wasn't setting any fashion trends, that's for sure, which was quite the opposite of many of his British compadres.