People may or may not be able to prove Obama is a native citizen and not foreign-born, evidenced by his actual birth certificate, wherever that may be.
An easier route to establish his disqualification for the Presidency (keeping in mind his father was a British/Kenyan citizen) is to state Obama is not a natural-born citizen according to what that phrase meant at the time it was written. So please read the following link...
http://puzo1.blogspot.com/2009/08/law-of-nations-and-not-english-common.html
The whole point is that there is nothing in the constitution that defines the term. Therefore, it will all be opinion, and they’re not going to make this decision based on one person’s opinion over another’s.
It will be made politically.