To address the "failure" thing though, actually it's a trope that every hero gets beaten up once or gets to the point where you think "now he's had it", but then manages to end up victorious. Think Superman and kryptonite, for example.
In fact it even spawned the related trope of
Heroic Second Wind.
Get apparently defeated to the point of being killed? Sure, that's one way to amp it up. Alucard does that more than once in Hellsing. In the very first episode he's machinegunned into hash by ghouls with MP5s. Does it make him any less awesome? Hell, no. It's actually just more awesome when he rises right back and shows them that, natch, they can't get rid of him that easily.
So let's look at what actually happens in the gospels: the Jews and Romans collude to try to kill and humiliate a righteous man (well, or at least you're supposed to believe he's righteous), but 36-48 hours later he's shown everyone that, natch, they can't get rid of him that easily. And in fact they played right into his
Batman Gambit and made his victory possible.
THAT is the actual story that is being told by the gospels.
Sure, if you remove key elements from it, in the name of some deluded just "knowing" which parts are actually historical, and change a few other elements too for good measure, you're left with a crap story that not many people would make up or like.
But then the same could be said about any other story. If you eliminate Alucard's rising after getting a few hundred gunshots, you're left with a crap hero that failed, nobody would make up such a crap hero, yadda, yadda, therefore Alucard must be historical. If you eliminate Superman's recovering after being trapped with kryptonite, you get a crap hero, nobody would make that up, etc, therefore Superman is historical. If you eliminate Luke Skywalker's escaping from the compactor in Episode IV... you get the idea, right?
Or lest someone complains that I can't compare modern stuff to ancient stuff, see Odysseus escaping from the cyclops, Inanna escaping from Hell, Odin's being right back to health after spending a week impaled and hanged, etc. Sure, if you remove their recovering for it, you get a crap hero that not many would make up.
But that's not the story told by the gospels. The story told by the gospels is of a superhero which doesn't fail at all, but which springs right back just when you thought you nailed him for good, and worse yet, it turns out you played right into his master plan by trying to kill him.
Would people make up THAT kind of hero and story? Well, actually, they still do all the time.