Let me just call bullshit on any "permanent Democratic majority" ideas right now.
It seems inevitable that the hacks of whichever party wins right these after nearly every election. They're always wrong. Always. I must have lived through a ten "permanent majorities" in my lifetime already, including all of the last three elections. The fashionable width of men's ties is more constant than the American "permanent majority" is.
I'm not going to bother arguing why they're wrong this time. (Go read this if you're interested.) In fact I'm not wasting another cognitive cycle on this.
I just want this post to exist so that 2n years from now, when stuffed shirts start talking about "permanent GOP majorities," as they inevitably will, I can link back to this to use as my i told you so.