Now, Skeptics and Religious Liberals have always used an array of arguments to undermine it's literal history. Likewise, Conservatives usually retaliate with some sort of "you can't say it didn't happen" shtick. In the end, neither side gets any closer to the truth of the matter. Want to see what I mean- here is an example.
A popular argument against the virgin birth is that it only appears in two of the Gospels. Conservatives argue that, because each of the stories were intended for a specific audience, blah blah blah. If you want to see an example of a Conservative answer, you can find one from JP Holding here. Now, I can understand certain miracles not being mentioned for this reason, but not one as significant Virgin Birth! By this logic, should we be surprised that the Resurrection was included, considering that everyone already knew about it? Furthermore, I don't think it really explains why Paul never mentioned it, even when he was evangelising. I am no Pauline scholar- but I am highly skeptical of anyone who puts politics before evidence of the miraculous. After all, the Gospels do include a particular story of women finding a particular empty tomb, remember?
As we can see, they are arguing that the Virgin birth possibly happened, not probably. They will say that, because so much of the Gospels are reliable, we ought to believe the parts in which there is little evidence, even when we'd expect more. But this is clearly pulling the cart before the horse! These stories should indicate the exact opposite- that we should be less trusting of our source, because they are willing to include things so obviously false! Anyways, at the end of Holdings essay, he makes an interesting and revealing remark.
"Objections against the validity of the virgin birth are based mostly on preconcieved notions - in the main, that the miraculous is impossible. There is no reason, other than pre-conceived notions, to reject it as historical; and to be fair, no reason other than own's own perceptions to accept it as such. It simply depends on our starting point.The reason I point this out isn't because of his spelling error (the "E" goes after the "I" in Preconceived). No, I point this out to show the reader what this is really about- that we atheists don't believe in miracles. It's never about whether or not their is sufficient evidence- it's just about having a philosophical prejudice against them. Now, I'll be the first person to admit that the Resurrection is usually denied due to philosophical prejudice. However, I hardly see how this relates to miracles like the zombies of Matt 27, of which there is no confirmatory evidence for. This just seems to me to be philosophical prejudice against Naturalism.