I think it's possible that some guy from Galilee lived and was crucified and all that, yeah. But the bit about being the "son of God" and rising from the tomb and all that? No, absolutely not. Complete and utter bollocks as far as I'm concerned.
Why do you ask that question on HN of all forums?
Yes, personally I believe He was real, and all that implies. The whole story is too complicated and fantastic to be fictional.
I have read a LOT of sci-fi, including loads of Asimov.
None of his characters are proven historical characters like Jesus. What most people find hard to believe is his claim to be God, his death, resurrection, ascension etc. I'm saying that I do believe those. Saying that all of that is fiction... I really find that hard to believe.
That said, although many would love a long discussion / argument about it here. For personal reasons I am not going to say more here today than I already have.
"To believe with certainty we must begin by doubting." You would have company in that position. But to remain forever in doubt is to waver between belief and unbelief. To which do you tend?