Inspired by: Fictional characters you have encountered
For better or worse I’m probably most similar to George Costanza, although I look more like Jerry.
Funny you should mention that. A few years ago I was always Radar O’Reilly. Now everyone calls me George Constanza. I gotta lose some weight.
A friend of mine thinks that I could be Tulip from the Preacher comic. I was raised by a single father in a household with lots of guns and I was taught how to use them. Sadly, I don’t have her killer body, but at one time I was a fairly good shot. 
While I don’t particularly look like her, I would have to say I can relate awfully well to Lisa Simpson.
Walt Feinberg in Trying Hard to Hear You.
Unfortunately, Mike Slakenerny. Except without the “sugar momma”, and I look nothing like him.
Well, I’m a visually impaired lawyer and martial artist, so I guess Daredevil.
Aside from the fact that I’m not Japanese, Hiro Nakamura is the best match to me I can think of.
In college I was sometimes compared to both Butters, from South Park, and Fry, from Futurama (the latter was helped by my friend who was essentially Bender, and our ever-present level-headed female friend.)
Except for the fact that I’m a man, I’m awfully similar to Elinor Dashwood from Sense and Sensibility. I don’t know whether that is good or bad, but there I am.
Someone once told me that I remind them of Freddie from A Different World, personality wise.
Much to my dismay, Sydney Carton from A Tale of Two Cities
Except on my really good days. Then I’m Silent Bob.
Ayumu “Osaka” Kasuga from Azumanga Daioh.
Law Abiding Citizen Josey Wales (no matter what the yankees called him).
Definitely him. Or Don Quixote.
So, you can bend space and time and you drive a Nissan Versa?
A woman I used to date once compared me to Howard Roark from The Fountainhead
I was not flattered.
I’m Shakespeare’s Beatrice from Much Ado About Nothing. I have a merry heart which keeps me on the windy side of care.
Mortimer Brewster from Arsenic and Old Lace mixed with… well, actually, Teddy Brewster from Arsenic and Old Lace. A picture in fact. 
Granny Weatherwax. I believe in Headology and the respect one is due for one’s wisdom and knowledge. 
(Although I’m married and considerably younger than Esme in the stories.)