There are two keys to this.
#1 Support Biden, and make sure he gets 2,000 plus delegates before any convention happens.
That way, he is the nominee and they cannot pull someone else out of the hat.

#2 Trump must demand debates, at least 4 of them.

If the democrats refuse, he should run a series of campaign commercials accusing Biden of dementia.
“I have offered to debate Joe Biden several times, but the DNC is hiding him because he has advanced dementia.”


MOLON LABE