1. IF BEFORE the Electoral College meets, McCain's electors from all states would be seated (since Obama would not have been qualified) and the vote would be 538-0 (Article II, Section I, Paragraph 3). This because Obama would not have been qualified in the first place. Biden would be VP since the 12th Amendment provides for the separate election of POTUS and the VP. Biden would be eligible and his electors would elect him. Therefore a McCain-Biden term.
2. IF AFTER the Electoral College meets and certifies him, but BEFORE inauguration, the 20th Amendment provides that, if before the time fixed for the beginning of his term, the President-Elect shall have failed to qualify, then the Vice President-Elect shall act as President until a President shall have qualified (McCain). The same scenario as in (2), above, would then likely apply.
3. IF AFTER the inauguration, the 25th Amendment would apply and Biden would be President and choose his VP (Senate confirmation) . However, McCain might and would be able to sue=based on the DNC fraud and demand scenario provided in (2) above, be applied. Or barring that, a new election.
4. Obama must be forcibly removed from the office and placed behind bars, especially since he was well aware of his fraud when the questions arose back before the DNC primary considering all his attempts to prevent all this information coming out in the Federal Courts. He can face a litany of punishments from jail to death in the extreme case according to the US Constitution. Anything he may have done in office would be null and void, if anyone dies under his RULE as a usurper of the Presidency, then death awaits him. All those involved with his usurpation of the office will also be in BIG DOO DOO with him. Can you say Iron bar hote.
5. Of Course, the SCOTUS can decide to avoid (1), (2) and (3), above and declare a fraudulent election and order a new election with verified candidates. This would implement Continuity Of Government Laws allowing Bush to remain POTUS until after the election. They could also require no new laws to be passed. Whatever happens the DNC Party would not be trusted for generations to come for their knowing attempt to usurp the Presidency, and may as a party become disbanded.
Whatever the outcome, be prepared, we may be witness to an unprecedented event in our nations history. GOD bless America and pray for your country, it could be a bumpy ride !