GOD FORBID Obama is not 2012 nominee

[The Mikado]

In that situation (which I think goes without saying is unthinkably horrible), it kind of depends on whether Biden even wants to run on his own.  He'd clearly decided on the VPship as a career capper.  I think he would run, but there's a definite possibility that he decides that he's just had enough and passes.

[The Mikado]

A tragedy like the assassination of the President combined with a likely weak GOP nominee would make Pres. Biden an automatic election.

Assassination isn't necessarily implied.  Air Force One breaking down over the Atlantic would serve the same function.

[The Mikado]

I'm curious as to whether that analysis applies equally to violent removal of the president and a tragic accident/natural causes death.  To be honest, the Secret Service is fantastic at their job (as well they should be: keep up the good work, guys) and I honestly think that the former is less likely than the latter.