In 1994, Archie Comics partnered with Marvel for a pretty strange mashup: Archie Meets the Punisher. While this is more of a "special edition" situation, there are a few things that indicate a superhero component of Riverdale is not out of the question.
First of all, it's pretty clear at this point that Marvel casts a wide net across the entertainment industry. With a vast TV and movie presence covering everything from The Avengers to Deadpool to Netflix's The Defenders, Riverdale could mark the latest exploit for the universe. Additionally, executive producer Greg Berlanti has an extensive history of superhero work. He's had his hand in Supergirl, Arrow, The Flash, Legends of Tomorrow, and 2011's The Green Lantern. If anyone's perfectly positioned to add a bit of superhero into Riverdale, it's Berlanti.
