The job of designing that character fell to Brian Bendis, who instead of ethereal unicorn horning turned to TV as a muse, basing Marvel's Ultimate Spider-Man on Donald Glover wearing Spider-Man pajamas in the season 2 episode "Anthropology 101" of Community.
Aaaand then, conspiracy theorist, political commentator, and the dead ringer for Santa Claus if he only delivered copies of Atlas Shrugged (at market price), aka Glenn Beck, discovered Marvel's new creation. In his own words: "Do I care if he's half-Hispanic, all-Hispanic? No. Half-black, half — I don't care, I really don't care … I don't really care. I don't care. I don't care, it's a stupid comic book," he said caringly, while caring, like actual non-caring people don't. To be fair to him, Beck didn't actually have anything bad to say about Miles. But he wanted his audience to really think about what it meant that there was a non-white Spider-Man out there … and then hopefully tell him cause he couldn't critically analyze a Garfield strip (the lasagna represents his lust, Glenn! It's so obvious!)
According to Bendis, Beck was the first celebrity to put Miles on the map. Soon the character was discussed by Stephen Colbert and Howard Stern, and Miles was on his way up.