I don't think that Rush has ever made such an inarticulate statement, but I think I get what you're trying to say. And, yes, that is true. That is because the Democrats have nothing of substance to run on. The economy is booming. They can't say, "I'll make the economy better!" They could point out the crisis in 'health care', but then, they created the crisis, so that would blow back on them. They could run on 'immigration', but then they've been saying all along that that wasn't an issue despite also admitting it is a serious crisis.
So, yeah. The left is in a tough spot. All they can do is point fingers and call names...which is why they won't win. They have nothing of substance to offer.