The Lone Ranger and Tonto
I am not an avid fan of comics, and know little about them. I have only seen a few episodes of The Lone Ranger, so my choice based more on the concept his character than familiarity of the books, TV series, or movie.
I don't know if he is properly counted in as a super-hero, since he has no super-human powers. However (imo) not having them adds verisimilitude to his story, where other super-heroes tend to lean towards fantasy. Not have extraordinary other than makes him more down to Earth hero. His marksmanship could be consider almost superhuman, but there are examples in history like Annie Oakley who was extremely talented.
The Lone Ranger is also not part of the Marvel/DC comical universe, so that's another reason he probably be overlooked as a superhero
per-se. But even so there are some similarities, he is a masked man who operates around (not with, or against) law enforcement. A vigilante who brings criminals to justice without killing them in the process. He has a friend (side-kick) that helps him narrowly escape perils. He has a back-story that involves a death of a family member (think Superman, Batman, and Spider-man) that profoundly changes the course of his life, and effects him. He has a calling card, in his case a silver bullet, that people identify with. He has a sense of right & wrong, a respect for life while exacting justice, and yet despite having those good qualities is, in a way, marginalized from society.