McCain was born to citizens, plural. Plus his father was serving in the military (Both Blackstone and Vattel have exemptions from "in the country" for militay and diplomats). Obama was born to one citizen and one alien, niether of whom were serving in the US military. Fails on both counts if born in Kenya, but still fails if born in Hawaii.
Plus under the law at the time, Obama's mother was too young for her foreign born offspring of one alien parent to qualify for citizenship. So if born outside the US, he's not a citizen at all, unless later naturalized. But still not a natural born citizen and thus not eligible to the office of President.
Excellent response to the other person who did not know presidential qualifications!