Now, I am not a trained theologian, so I can't really conclusively comment on the success of any of these strategies. However, that doesn't mean I can't hold a inconclusive opinion. For one thing- how can we determine which Religion is correct if they all make similar claims? If every miracle ever documented were done for and by Christians, than that would be good evidence that Christianity is the true faith. However, what we see instead are many miracles being claimed by many religions. The only possible scenarios I see are that, either God allows miracles to happen that inevitably draw people away from Christianity, or that these things all have natural causes. Well... I guess one can argue that there exists an all loving, Universalist God that does miracles for everyone. But even this scenario doesn't seem to fit in with the Christian concept of hell and atonement, does it? In the end, it just seems intuitive that all these miracle stories are false.
Also, even if we granted that miracles occur in Christianity alone- one would have to ask why they even exist in the first place? What is the criteria in which someone is allowed to witness a miracle, and someone is denied that opportunity? Because it seems to me that the person who witnessed a miracle will have a better chance of being/remaining a Christian than the person who does not- giving them an unfair advantage. A Theist could claim that God works in mysterious ways, or that he rewards people who would've believed anyways, using his Omniscience. Answers like these are clearly sound- but that doesn't mean they are good. For one thing- they are both unfalsifiable, and cannot ever be tested or proven false.
Just to conclude, I wanted to mention NDE's again- since they are generally considered the best evidence for an afterlife. I have argued before that, since NDE's occur to members of other faiths, they are probably of naturalistic origin. Ed Babinski argues this at length during the conversation about miracles he had on Victor Repperts blog.
"Same with Near Death Experiences, the majority of which are positive, even for people who do not become orthodox Christians. In fact Mormons have a journal devoted to recording and studying the Near Death Experiences of Mormons (some of them saw Lincoln in the afterlife, and guess what, Lincoln converted and became a Mormon after he died), which sometimes are quite detailed and involve a trip to a very Mormon-looking heaven. Betty Eade wrote several books about her Mormon NDE that were on the bestseller lists about ten years or so ago. "Surprisingly, many commenters agreed with him that Miracles can't be used as evidence for the existence of God! I chalk that up as a victory for Atheism.
HT to Russ, Ed Babinski and the many other anonymous commenters