However, speculation along that line is often considered rather gauche, because if you think Jesus of Nazareth is who Christians think he is, what's the problem with miraculous explanations? and if you don't accept miracles, you're not likely to think the stories are true anyhow.

That doesn't say much about how Jesus might have raised the dead! But debunkers (and some Christians, like Borg or Funk or Crossan ) discount those stories anyhow.

Typically, someone who doesn't believe in miracles will either refuse to accept the truth of things that aren't explainable within a naturalistic worldview--"they never happened!"--or invoke improbable coincidences or mass hypnosis (which are the same thing). Either option is open.

The only bit explainable without invoking improbable coincidence ("the school of fish just happened to be there" or worse, "the storm ended just as he commanded it to do so") or equally improbable mass hypnosis ("through the power of his mind he convinced a boatload of fishermen that he was walking toward them across the lake") is the feeding of the 5,000. The debunkers' (and liberal Christians') explanation is that Jesus, through the force of his personality, led people to share food they had brought along with others who had none. Whether this makes sense in the context of the Biblical story is up to you.

Short answer: "No."

• Virginal conceptions do happen in other species, but there is no medically verified report of any such occurrence in humans.
• The only theory I've ever heard of that attempts to explain the bodily resurrection of Jesus in naturalistic terms (as opposed to denying it) is Schonfield's The Passover Plot, and its argument is garbage.
  C'mon... a man who went without food for at least 24 hours and was thoroughly flogged before the excruciating experience of crucifixion, faking a death on the cross right in front of Roman soldiers who knew what death by crucifixion looked like and how to make certain of it, then walking (!!) out of his tomb on severely lacerated feet between 36 and 40 hours later and convincing his followers that he was triumphantly risen from the dead?? Give me a break.
• Debunkers typically explain the reported post-resurrection appearances as wishful thinking or outright lies--alternatively, what we now call "urban legends."

  Liberal Christians who don't accept the Resurrection as described in the New Testament explain that Jesus was somehow immaterially "present" to his followers after his death, and this led them to describe him as "risen from the dead."

  N.T. Wright (see his book with Marcus Borg, referenced above) has done a good job explaining how anachronistic any such views are. Jews in Jesus' cultural milieu would simply not have thought that way any more than they would have described the universe in terms of bubble cosmology.

Long answer, "No, because..."

By definition, miracles are extraordinary (often one-of-a-kind) events without precedent or natural explanation, and they are not reproducible. By this, I mean that, while miracles (or miracle stories, depending on your taste) may cluster around one person or a few people, it is not true that anyone with the requisite training or performing the requisite ritual(s) will be able to observe the same results. (That's what distinguishes miracle from magic, by the way. In magic, as in science, in principle anyone can get the same results as long as they fulfill whatever requirements.)

On the other hand, science is concerned with what can be observed by anyone, anytime, anywhere. (This is, of course, an oversimplification-- but not by too much.) See our FAQ page, especially the Life FAQ and the Evolution FAQ.

Therefore, science cannot say much that's meaningful about miracles per se; hence the answer to your question is "no." Q.E.D. Or, to quote one of our founders (Lynn Bry), "[talk of miracles] is not subject to the hypothesis-driven, nor self-correcting aspects of scientific endeavor." See this previous answer.