Biden to Withdraw - Hillary to Replace Him?

File under "rumors"  at least for now.

In 1988 Joe Biden had two brain aneurysms. Serious to be sure but he's been healthy for twenty years. Good for him. However, there is a rumor that he will withdraw after the VP debate claiming health concerns and be replaced as the nominee by Hillary Clinton. Such a move could be a game-changer though hard to pull off should the rumor become common knowledge in advance of the debate...