Until new elections. It would be VP if he had to leave office due to illness, death, etc. But being ineligible makes the election fraudulent.
I was looking for “chapter and verse” in the US Constitution, but didn’t find it. I’ve seen it before, though.
I don’t know if it makes the election fraudulent, but it would seem that the ineligible votes would be thrown out, therefore McCain would garner the most votes...hence......