ETA And I am not arguing against the existence of Jesus, I think it is obvious he existed. We keep time by him for goodness sake.
People often treat the question of whether Jesus existed as a question of historical fact, rather than a question of semantics. But I think it's clear that the semantic issue is essential.
If "Jesus" means somebody who fits the exact, literal description of the character 'Jesus' provided in the New Testament, accurate in every detail, there is about a zero percent chance that Jesus actually existed.
If "Jesus" means somebody whom at least some of the stories that the character 'Jesus' in the New Testament were based on, there is about a 100% chance that Jesus actually existed. (In fact, a number of Jesuses likely existed.)
So whether Jesus actually existed necessarily comes down to the semantic issue of what we mean by "Jesus." What list of attributes must a person have in order to qualify as the (or a) historical Jesus? Must he have been born in Bethlehem? Must he have been a carpenter from Galilee? Must he have given the Sermon on the Mount? Must he have walked on water? Must he have fed a multitude with seven loaves and fish? Must he have been crucified by Pontius Pilate? What if a person meets only three of those six criteria? Does he then qualify as the historical Jesus? (Does it matter which three?)
There are hundreds of claims made about Jesus in the New Testament. Whether Jesus existed or didn't exist is not an all-or-nothing proposition. It's very likely that the historical person who most closely resembled the Biblical Jesus fits substantially more than zero of those claims, but substantially fewer than all of them.