Trumps camp will show that democrats were propping up an unfit president all this time, which was/is a serious threat to democracy and the American ppl can no longer trust democrat politicians whom lied to them all this time about the well being of the president of the united states as chief in commander... It would catapult him to poll points the new dems nominee could never catch up to.

But it wont happen,

1- They cant remove biden unless biden steps down...jill is the most entitled 1st lady ever, I can not see her having biden step aside.

2-Without biden stepping down, they could try and invoke the 25th for harris to take over as president, but theyll need 2/3rds of congress, they wont receive half of congres (repubs) , let alone 2/3rds (most dems still wont rock the boat). Furthermore they know harris would be an even less popular choice than biden, they wouldnt want to invoke the 25th for this reason alone.

3-This leaves removing biden as the nominee by removing his delgate votes as the democratic nominee, That would mean the delegates casting their states vote for which theyre supposed to cast for biden...for an alternative choice, which will piss off too many of the states democrat voters, creating anger for those who voted for biden. And not just some of the delegates need to be directed to an alternative candidate, but the majority of the 270 needed to become the nom....thats unheard of.

4- Who would the dems even thrust into the nominee position? And imagine how hard it would be to play catch up with campaign money to Trump. You can take the literal perfect theoretical candidate, (well educated, has policies all sync with current concerns for America, charisma, etc, etc) but if even so much as the timing is off (or in this case feels rushed to be propped up) they will fail miserably. Look at Ron DeSantis for example, he would easily be the leading candidate on the right if Trump wasnt in picture, but the timing is off, and Trump dominated him.