So the answer was... Elect in a president who long lost his mental faculties. Okay.
Not sure why this is so complicated --- blame the DNC and party elites, not the population that voted for Trump.
If the DNC was trying to win, they would have never let Biden run for re-election, and then they would have never let Harris become the candidate without a primary.
The Democrats literally told the US population Trump was going to destroy democracy in America, and then created a situation that enabled him to win in a landslide.
The Democrats loss fair and square. They should have spoken up a lot sooner. Everyone on the inside knew that Biden was incompetent. If they had a real primary would Kamala ever have been the nominee?
The Democrats lost strongholds like Miami of all places. The dumbest thing they did was go against the tech industry who have always been their biggest supporters. Would Republicans go after Evangelical Christians or the NRA?
They gave people no reason to support them.