It's not really an objection, it's more of an observation.
While scientific research has never really shown that resurrection is impossible, it has also never really shown that it is possible.
It's very easy to say something has happened from something other than natural causes, because it can never be proven nor dis-proven.
There is no illustration, that can be applied, it is merely a matter of faith. If it was believable, one would assume that throughout history, more people would have become believers.