"There is no evidence for a historical Jesus"
There are the two references by Josephus
http://en.wikipedia.org/wiki/Josephus_on_Jesus
Now I'd certainly not suggest that these are both entirely accurate - indeed some of it seems to be very crudely edited.
However it does constitute evidence.
Given the Age of Mark's Gospel and the number of other early writings it seems improbable that Jesus was an invented character.
Indeed why would it be necessary? 1st century Judea was swarming with healers, wise men, mystics, miracle workers.
So I'd say that there is some evidence but there is no evidence that he was ficticious