I find that highly unlikely.
Considering that the majority of the Electors will be Dimicrats it is very unlikely that they will put a conservative Republican in the VP seat.
More likely by far is that you will have a Hillary/Biden or vise versa.
I find that highly unlikely.
I was envisioning a scenario where Party solidarity would hold, for Biden, on the Presidential race, but would break down for the VP, giving Palin a plurality.
But the rules state that the VP needs a majority, or the race is thrown to the Senate, to decide between the top two candidates. And that would still go to the Dem, no matter which Dem was offered up.
That raises an interesting scenario, though. If Obama is disqualified, and the Dems electors split on both races, both are thrown into the House and Senate. But the House decides on the President from the top three candidates, and the Senate decides on the VP from the top two. So if the House also deadlocks, with, for example, Biden and Hillary and McCain each attracting sufficient votes that none of them can gain a majority, the Presidency devolves to the person the Senate had chosen for VP.