It's still going to backfire tremendously. They have already done the main primaries. They told Bernie he was out. Bernie supporters aren't going to vote for another candidate to replace Biden, as they were shafted. They would have to break their own rules to bring in a new candidate who never primaried. This is going to piss off all of the Biden supporters so they aren't going to vote. I feel like if they did a switch, it's still going to be the weakest turn out ever for the Dems.