They could start by shedding any hope of capturing those voters. I can tell you with 100% certainty, based on trump being a convicted felon, there is no attack that will flip them. You have to reach outside current demos and bring your message to them. If they can't learn this obvious fact thats been lingering for 8 years (shoot someone on mainstreet) they are useless as a political power.
Next is the message. Obviously it has to be about change. Where Harris again failed by clinging to bidens record. The DNC needed to drop current dogmas and level. They would have started by talking like a normal fucking human who doesnt have a scripted line and strategy for everything. Then they would lay out the facts. This is what 'government can do' and this is what 'government can't do'. This is what YOU the voters need to do to get governement to do what YOU want. Then address what they want! FINANCIAL INDEPENDENCE. THEN LAY THEM WITH THE FUCKING PEOPLES ELBOW. "THE PEOPLE HAVE TO BLOW UP THE POLLS TO GET THE FREEDOM OF FINCIAL INDEPENDENCE, IF THERE ISNT COMPLETE HEDGEMONY IN ALL BRANCHES OF GOVERNEMNT THERE WILL NEVER BE MEANINGUFL CHANGE."
Promise fincaial independence, promise people will never get it if they don't show. Then we either got as far as the line, "I own a gun" or the people show up. Either way, you ran an honest, noble campaign.