That can only be done by the Cabinet, which is all Dems. If invoked, and Biden does not challenge it, Republican Speaker of the House Mike Johnson becomes VP. This would shift the balance of power in the Senate to Republicans, as the VP holds the tie breaker vote. They also do not want a Republican VP in the White House observing anything they do or discuss.
It will not happen.
It is too late for Biden to be replaced on most state primary ballots. Biden will go through the entire primary process. At the convention expect him to relinquish the nomination. The Dem powers will then UNDEMOCRATICALLY select a replacement to run in the general election.
They have spent almost zero dollars on primary campaigning. In the meantime Nikki Haley has burned up +$70 million and rising on a losing cause. The Republicans have no idea who will be the Dem candidate and will have little time to research and run negative ads.
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