These verses:
1 Co 5:1-5
5 It is reported commonly that there is fornication among you, and such fornication as is not so much as named among the Gentiles, that one should have his father's wife.
2 And ye are puffed up, and have not rather mourned, that he that hath done this deed might be taken away from among you.
3 For I verily, as absent in body, but present in spirit, have judged already, as though I were present, concerning him that hath so done this deed,
4 In the name of our Lord Jesus Christ, when ye are gathered together, and my spirit, with the power of our Lord Jesus Christ,
5 To deliver such an one unto Satan for the destruction of the flesh, that the spirit may be saved in the day of the Lord Jesus.
KJV
demonstrate that it is possible to be saved and apostate (Walking contrary io the Holy Spirit's leading) at the same time.
It is NOT OUR JOB to determine the truth of Obama's claim to Christian faith. That is a task God has reserved for Himself.
We can empirically discern that Obama is an arrogant self-seeking liar with little interest in the well-being of our country; but we are not called to judge his faith.