"What doctrinal beliefs delimit a 'Christian'? "
I don't think doctrinal beliefs delimit a Christian. What delimits a Christian is repentance of sin, faith in Jesus to save you, and thereafter an indwelling of the Holy Spirit. That said, this is grounded by at least some obvious doctrinal beliefs, such as Jesus really existed, really was the Son of God, and really rose from the dead (the last one being essential as described by Paul).
I certainly agree with all the miracles of the Bible. I believe in the supernatural (I believe in God after all) so believing in the virgin birth is no issue. And we have no evidence to the contrary. (I am not Catholic so I don't have any opinion on their extra-biblical doctrines such as the immaculate conception). But we do seem to have evidence on the contrary that we were created as is just 6000 years ago, and that needs to be evaluated.
Edited by Pete OS, : added a missing 'have'
™ Version 4.2
