First, the Democrats gave Trump a great gift by completing the ongoing radicalization of their party under President Obama. After 2008, it was no longer a party of the working and middle classes, but a lopsided political pyramid.
On top were the cynical elites who turned up in the WikiLeaks John Podesta email trove: self-important media members, Ivy League grandees, Silicon Valley billionaires, Wall Street plutocrats and coastal corridor snobs. They talk left-wing but live royally. They court minorities to vote in lockstep, then deride them in private. The vast lower tier of the party comprises government employees, the poor, minorities, and the millions dependent on state and federal assistance. The Democrats in between were ignored, and so they kept fleeing the party. Look at the red/blue map of the election. Democratic strength retreated to the inner cities and the rich coastal suburbs.
The Democrats also, in suicidal fashion, stoked racial chauvinism, or the notion that one's tribe should transcend all other affiliations. After pandering to various minority groups, Hillary Clinton apparently believed that they suddenly would forget her emphasis on race and ethnicity to vote for her, a 69-year-old white multimillionaire.
But the Democrats learned a bitter lesson in 2016: Obama's left-wing, rich/poor ideological agendas do not appeal to most of the country. Despite a hard progressive agenda, Obama was able to win two terms by relying on racial and ethnic solidarity, earning record numbers of Latino and black votes.
The logic of such a formula could not be easily transferred to a non-minority Democratic candidate. So Clinton lost key blue states of Michigan, Pennsylvania and Wisconsin because minority turnout in cities such as Detroit, Philadelphia and Milwaukee fell off from 2008 and 2012.
Worse for Democrats, by pandering to tribal solidarity, they polarized the white working classes. When physical similarity is touted as the best argument to vote for someone, it green-lights everybody to do the same -- including huge numbers of less affluent whites who voted for Trump.
Trump took advantage of these openings. By reformulating the old Republican messages to include so-called fair (rather than free) trade, by leaving Social Security alone and by promising to create more jobs, Trump plucked millions of lower- and middle-class voters from the Democratic Party.
Republican elites may have been appalled that Trump blasted global trade agreements and promised to punish corporations that outsourced jobs overseas. But those who have been left out of the globalized economy flocked to that message after not warming up to John McCain and Mitt Romney in earlier presidential elections.
Trump's populism also appealed to a surprising number of blacks and Latinos. Although Trump was even richer than some multimillionaire Republican nominees of the recent past, he posed as a man of the people, eating fast food and speaking in a Queens accent.
For many non-whites, Trump's message was more about class than race. Inner-city dwellers share many of the same worries as the poor whites of the Ohio Valley and southern Michigan. Some blacks have more in common with poor whites than with Colin Kaepernick or Van Jones. And many whites have more in common with less affluent blacks and Latinos than with Mitt Romney or Jeb Bush.
These populist economic interests had been ignored by Democrats and Republicans, as coastal-corridor economies made 30-somethings in Silicon Valley and on Wall Street multimillionaires -- with only crumbs left for those who work with their hands.
In other words, Trump miraculously won the Electoral College despite adversarial media and hostile Democratic and Republican establishments. He ran with relatively little campaign spending, virtually no ground game, few political handlers, little celebrity backing and few establishment endorsements. And he won because he rewrote the traditional rules of red/blue presidential politics.
Democratic Party chiefs slammed Trump as a bigot. "Never Trump" Republicans trashed him as a protectionist and populist rather than label him a true conservative. Some elite Democrats rightly feared that he might revolutionize politics by stealing minority and working-class voters from Democrats on shared class concerns that transcend race. Some elite Republicans worried that he could win new converts who weren't concerned with whether the Wall Street Journal found him to be an apostate and so often a vulgarian.
The strangest irony of all?
Establishment Republicans who hated Trump sounded a lot like establishment Democrats.
In sum, the billionaire Trump thinks he can forge a new kind of "Republican" majority, to the chagrin of elite Democrats and elite Republicans alike.
And he could be right.