It’s almost a violation of the laws of the political universe. By definition, a vice president looking to inherit the Oval Office has been part of the outgoing administration, and there’s only so much distance that a vice president can credibly put between them and their boss. (Often they try to find a way to praise what has happened, while hinting that things will be different, as when George H.W. Bush urged voters to “choose the horse that’s going the same way,” even as he’d pursue “a kinder, gentler nation.”)
But this time, the sudden elevation of Kamala Harris, along with the identity and character of her opponent, has — for now at least — made her the candidate who embodies change, no matter how little her policies differ from the current president. That this happened by accident rather than design does not make it any less potent as a political asset.