By Paul Krugman – New York Times.

Maybe we need a new cliché: It ain’t over until Carly Fiorina sings. Anyway, it really is over — definitively on the Democratic side, with high probability on the Republican side. And the results couldn’t be more different.

Think about where we were a year ago. At the time, Hillary Clinton and Jeb Bush were widely seen as the front-runners for their parties’ nods. If there was any dissent from the commentariat, it came from those suggesting that Mr. Bush might be supplanted by a fresher, but still establishment, face, like Marco Rubio.

And now here we are. But why did Mrs. Clinton, despite the most negative media coverage of any candidate in this cycle — yes, worse than Donald Trump’s — go the distance, while the G.O.P. establishment went down to humiliating defeat?

Personalities surely played a role; say what you like (or dislike) about Mrs. Clinton, but she’s resilient under pressure, a character trait notably lacking on the other side. But basically it comes down to fundamental differences between the parties and how they serve their supporters.

Both parties make promises to their bases. But while the Democratic establishment more or less tries to make good on those promises, the Republican establishment has essentially been playing bait-and-switch for decades. And voters finally rebelled against the con.

First, about the Democrats: Their party defines itself as the protector of the poor and the middle class, and especially of nonwhite voters. Does it fall short of fulfilling this mission much of the time? Are its leaders sometimes too close to big-money donors? Of course. Still, if you look at the record of the Obama years, you see real action on behalf of the party’s goals.

Above all, you have the Affordable Care Act, which has given about 20 million Americans health insurance, with the gains biggest for the poor, minorities and low-wage workers. That’s what you call delivering for the base — and it’s surely one reason nonwhite voters have overwhelmingly favored Mrs. Clinton over a challenger who sometimes seemed to dismiss that achievement.

And this was paid for largely with higher taxes on the rich, with average tax rates on very high incomes rising by about six percentage points since 2008.

Maybe you think Democrats could and should have done more, but what the party establishment says and what it does are at least roughly aligned.

Things are very different among Republicans. Their party has historically won elections by appealing to racial enmity and cultural anxiety, but its actual policy agenda is dedicated to serving the interests of the 1 percent, above all through tax cuts for the rich — which even Republican voters don’t support, while they truly loathe elite ideas like privatizing Social Security and Medicare.

What Donald Trump has been doing is telling the base that it can order à la carte. He has, in effect, been telling aggrieved white men that they can feed their anger without being forced to swallow supply-side economics, too. Yes, his actual policy proposals still involve huge tax cuts for the rich, but his supporters don’t know that — and it’s possible that he doesn’t, either. Details aren’t his thing.

Establishment Republicans have tried to counter his appeal by shouting, with growing hysteria, that he isn’t a true conservative. And they’re right, at least as they define conservatism. But their own voters don’t care.

If there’s a puzzle here, it’s why this didn’t happen sooner. One possible explanation is the decadence of the G.O.P. establishment, which has become ingrown and lost touch. Apparatchiks who have spent their whole careers inside the bubble of right-wing think tanks and partisan media may suffer from the delusion that their ideology is actually popular with real people. And this has left them hapless in the face of a Trumpian challenge.

Probably more important, however, is the collision between demography and Obama derangement. The elite knows that the party must broaden its appeal as the electorate grows more diverse — in fact, that was the conclusion of the G.O.P.’s 2013 post-mortem. But the base, its hostility amped up to 11 after seven years of an African-American president (who the establishment has done its best to demonize) is having none of it.

The point, in any case, is that the divergent nomination outcomes of 2016 aren’t an accident. The Democratic establishment has won because it has, however imperfectly, tried to serve its supporters. The Republican establishment has been routed because it has been playing a con game on its supporters all along, and they’ve finally had enough.

And yes, Mr. Trump is playing a con game of his own, and they’ll eventually figure that out, too. But it won’t happen right away, and in any case it won’t help the party establishment. Sad!