H. Clinton made the mistake in 2016 of not campaigning everywhere. DNC made the same mistake in many, many elections over the years.
The DNC needs to campaign in every possible place, obviously they need to have a bigger spend, and a bigger push in swing states, but the more they campaign everywhere, the more down ballot Dems get attention. They need more than a president to get shit done.
Start adding more progressives to the house and (maybe someday) the senate, and we’ll start turning this ship around.