He has one passage, though, which -- while making complete sense -- I'm not sure sure if I agree with, though purely because of personal experience. He writes -- "It may not play out quite that way with Trump because due to gerrymandering and polarization, more Republicans are probably in 'safe seats' and less afraid of losing them."
While I do fully agree with that in theory -- and in some reality, since he's quite right that gerrymandering and polarization have both definitely increased in the intervening 40 years -- my own personal perspective says otherwise. Let me explain:
I grew up in an extremely Republican Congressional district, in the northern suburbs of Chicago. There were several liberal patches, but mostly it wasn't just Republican but conservative. Very conservative. No gerrymandering was needed to make it more so. It was conservative Republican, period.
How much so? When I was a kid, our Congressman was Donald Rumsfeld. Yes, that Donald Rumsfeld. (It was the 13th District, as appropriately-numbered as could be.) The only reason he left the office was because he was hired by the Nixon Administration to head the Office of Economic Opportunity (can you imagine?!), which was Cabinet rank. While you would think it would be a joy to finally have him gone -- no, no, you have forgotten that this was, is a very conservative district. And so, worse -- if that would seem possible -- to replace him the district next elected a fellow named Philip Crane, a man so right-wing he made Rumsfeld look semi-moderate. (Really. I've talked to people from elsewhere in the country who, 30 years later, remembered hearing of Crane and how profoundly conservative he was.) Redistricting fortunately moved him into an even more conservative district. I'd say that this was a relief, but then openings for Congressman got us Phillip Crane after Donald Rumsfeld, so one didn't inherently look forward to such things.
The point is that this was a deeply Republican and conservative district. Almost as safe a red district as you could imagine. And that meant that with its House seat now open, it was easy pickings.
But then Watergate hit, all the Republican scandals followed, Administration officials went to jail, Vice President Agnew had resigned, and Richard Nixon resigned in disgrace.
In the midst of this highly-conservative district, the very liberal and quite wonderful Abner Mikva ran for this 13th District opening to the House of Representatives. And (are you ready?), he actually won the profoundly red district in a squeaker. In fact, he was so well-regarded that he even won re-election two years later. But it was another intensely-close race, decided again in the hundreds of votes I think, and it being such a conservative area, he knew it would never be a safe seat, so when new President Jimmy Carter offered him a federal judgeship -- a lifetime appointment -- he wisely took it. It was a loss for our district's loss, but a good thing for the American judicial system.
(Actually, you probably know of Abner Mikvah. Some people I've spoken to three decades later remember him on purely political grounds. But there's another reason. As I wrote here a while back -- If you've seen the movie, Dave, with Kevin Kline as a look-alike to the president, you will no doubt recall the final scenes that come after the real, and crooked president has passed away. And so, the admirable Vice President is sworn into office on the White House lawn by the Chief Justice of the Supreme Court. It's a tiny moment in the film -- but the Chief Justice is played by...Abner Mikvah!)
The point here is that, while I agree with the assessment that gerrymandering and polarization has made seats much safer today than during Watergate, I always remember that during Watergate that 13th district was as safely Republican and conservative as a Republican could wish. And it not only voted for a Democrat during the GOP scandal meltdown, but for an especially-liberal Democrat. That's how outraged the public was.
That may not happen in today's landscape. But if I was a Republican, I wouldn't count on it. Besides, it's important to remember this, too: there are 24 Republican districts that are considered "at risk," not remotely safe. If only those 24 change and go Democratic, then the House of Representatives switches to Democratic control. And there are 214 other Republican seats at the moment, on top of those 24 at risk. The Senate only has to flip three seats. It's true that more Democratic Senate seats are up for election than Republican, but then Democrats aren't facing massive political scandal...
So, who knows. But it's important to remember the Lesson of Abner Mikvah. And that lesson is not just that a very liberal Democrat won in a deeply conservative Republican district the last night a president's entire administration was embroiled in massive scandal, leading to resignation, but that in Hebrew, a "mikvah" is a ritual bath of cleansing.