Boy, that might be just the ticket though, given the economy being well, employment high, and people be generally optimistic about the economy overall.
Clear out all the embarrassing and chaotic aspects of Trump, deal with the border more humanely (which mostly means "very similar" but be a Democrat) and don't break anything.
The economy always matters, and the Democrats are playing to an audience I'm not sure is big enough, those that feel like our very economic system has utterly failed them.
Their key is to convince voters that their neighbors are doing much, much worse than they are, because most people think they're doing pretty well. I do actually think that has a chance to work, but it's still going to be a real finesse job to convince people to rip up and start over in an economy that they're overall satisfied with.
Honestly, I think there's a case for a Democratic moderate, if there ends up being any, that they'd be BETTER for maintaining the current economy, due to Trump being so dumb, chaotic and unpredictable. I don't know that there's a practical way to make that work though.
