Religious persuasions of Comic Book Characters...

WASP type, but beyond that hard to say. Spiderman might be Unitarian, tho. So much doubt.

you can tell by his parents' Hebrew names.

(Not to say that one can't convert.)

It's Old English for "sharp" or "cut" I think.

Jor el and so on. El is Hebrew for "lord."

Jerry Siegel and Joe Shuster were both Jewish.

But Superman, the character, isn't Jewish.

The creators were Jewish and some say that they used the "Jewish immigrant" story trying to fit in the American society just like their parents did. At least for the initial concept.

Not only the parents of superman and superman's names were Hebrew but "Kent" is one of many americanizations of the name "Cohen."

So I am sure superman spins the dreidel.

From Wikipedia: The modern name of Kent is derived from the Brythonic word Cantus meaning "rim" or "border".

...as an Americanized version of "Cohen." The Wikipedia article about superman suggests:

"Furthermore, the surname Kent, in early 20th century real life, was a common Americanization of 'Cohen,' and Clark Kent's wimpy, bumbling persona strongly resembled the classic Yiddish schlemiel."

Wolverine seems interesting.

I would say Comic books tend to have a lot of Atheists and Agnostics, namely ebcause there are a lot of Scientists. Plus there is the whole awkwardness of Faith when, very often, the Gods and Godessess people used to worship are the people having Coffee with you in the Hall of Justice or Avenger's mansion.

Here is on odd take: Is Doctor Strange, aka the "sorcerer supreme", a Pagan clegy, or, because he knows the way these "magic" entitiies work, is he a Scientist, dealing with just a slightly more complicated group of people and forces?

Also, one last point about Comics..

A story I read when I was young had the Justice League beating a Witch, that turned out to be a High-tech alien using holograms. Now, Barry Allen, aka the Flash, was a police scientist, so he said:

"This proves to me that what people call Magic is nothing more than undiscovered science!"

Then, Hal Jordan, aka Green Lantern, tells Barry

"maybe Science is just unacknowledged magic..."

And I can only imagine what would have happened if DU was around at the time

...which was more of a play on how he looked like the devil but was down with the lord, but other than that I don't really remember religion being a big part of the storylines when I read comics back in the 60s and 70s.