Rather than trying to win over the Republican Party’s power brokers, Donald Trump is at war with them—and he’s winning. Photograph by Mark Peterson / Redux

Primaries are tricky to cover. By their nature, they exaggerate divisions within a party, bringing to the surface the most extreme elements in a political coalition. What, in the frantic year leading up to the nomination of a Presidential candidate, look like mass movements that are on the cusp of taking over a party often turn out to be nothing more than gyrations in the polls, even if they are extended ones, or the inflation of one noisy slice of the electorate that gets disproportionate media attention.

The history of Presidential primaries is the history of small and exciting movements that quickly get snuffed out. In 1996, when the Republican Pat Buchanan won the New Hampshire primary, his platform of protectionism, isolationism, and anti-Washington populism seemed to be near ascendant, but Bob Dole, the ultimate Washington insider, easily defeated him for the nomination. Four years later, when John McCain defeated George W. Bush in New Hampshire, many pundits argued that McCain’s reform conservatism, which coupled a hyper-interventionist foreign policy with left-leaning economic views, would redefine the G.O.P. But Bush easily regrouped and defeated McCain, partly by emphasizing his insufficient commitment to cutting taxes. McCain’s Wilsonian views on foreign policy did eventually prevail in the Bush years, but in 2008 he ran and won the nomination as a fairly conventional Republican. For a moment in the 2012 campaign cycle it seemed like Michele Bachmann was going to remake the G.O.P into a vehicle for the religious right, but she never made it past Iowa, and Mitt Romney, a Mormon who was viewed warily by many evangelicals, won instead.

The last real outsider to take over a party was Jimmy Carter, in 1976. In a piece I wrote for the magazine on the 2012 race, I cited the reaction of Averell Harriman, the former governor of New York, when he learned of Carter’s impending victory. “Jimmy Carter? How can that be?” Harriman said. “I don’t even know Jimmy Carter, and as far as I know none of my friends know him, either.” But even Carter was an elected official (a state legislator and one-term governor from Georgia) and had been active in the Democratic National Committee. On the Republican side, you have to go back to Senator Barry Goldwater’s nomination, in 1964, to find a Republican who captured a party against the will of the party’s élites.

Donald Trump’s attempt at a hostile takeover of the G.O.P. is astonishing in its breadth. He is not just competing against a large field of candidates for votes in the primaries; he is at war with nearly every power center in the Republican Party—and he is winning. How is he doing it? One of Trump’s strengths is that he has effectively co-opted a conservative counter-establishment that has been growing during the Obama years, which has seen the rise of a movement on the right that dislikes Republican leaders almost as much as it dislikes the President. Trump is finding that the anger of this movement can be harnessed to attack a broader array of targets than just Washington politicians.

Take, for instance, Trump’s war with Fox News. The fight started when Megyn Kelly, the Fox anchor and one of the moderators of a Republican debate last August, asked Trump about his pattern of insulting women with terms like “fat pigs, dogs, slobs, and disgusting animals.” After the debate, Trump seemed to make Kelly’s point by attacking her in a vulgar way. For months he has continued to belittle her, despite on-again, off-again truces reportedly negotiated between Trump and Roger Ailes, the head of Fox News. Certain shows on Fox—though not all of them—soon became hubs of anti-Trump voices, and Trump, who is well-known for holding grudges, responded by publicly attacking Fox pundits by name, especially George Will and Charles Krauthammer.

This week, according to Fox News, Trump’s campaign tried to muscle Kelly out of her moderator chair for a debate on Thursday. The fight descended into a volley of schoolyard taunts between the two sides, and Trump pulled out of the debate and said he would organize his own competing event, in Iowa, to benefit veterans. Trump’s campaign continued to escalate its attack on the network. “Fox News Corp. has donated over $3,000,000.00 to the Clinton's [sic]. Makes you wonder what goes on behind the scenes....” Daniel Scavino, Jr., Trump’s senior adviser, tweeted. The number apparently combines donations to Clinton political campaigns and corporate philanthropic donations to the Clinton Foundation, though Scavino’s sources and methodology were unclear.

Fox News has long been considered the most influential news organization for conservatives. In an e-mail newsletter today, the longtime Republican consultant Alex Castellanos called Fox “the most powerful Republican institution in contemporary American politics” and “the stage on which Republicans play.” He added, “Most Republican candidates kneel before it, supplicants hoping to sip airtime from its chalice.” No matter how unfair the coverage, few Republican candidates dared to launch the kind of assault that Trump and his aides have initiated. It was considered a death sentence in a Republican primary. Similarly, Trump has been attacking, and been attacked by, the main organs of conservative opinion—National Review and The Weekly Standard—which were previously considered the enforcers of conservative ideology and institutions to be flattered rather than condemned.

But Trump has found media support in other places: Breitbart News, the Web site that has become so pro-Trump that other conservatives mock it as “Trumpbart.” An article on Breitbart today cheered Trump’s decision, noting, “The network’s treatment of Trump has indeed only reinforced the suspicions many Fox News viewers have had about the network’s move toward the center.” Similarly, populist radio and TV personalities like Rush Limbaugh, Ann Coulter, and Laura Ingraham are steadfastly pro-Trump. And, of course, Trump has his nearly six million Twitter followers, which he has sometimes described as better than owning his own newspaper.

Similarly, while no governors or members of Congress—or, really, any prominent elected officials—have formally endorsed Trump, he has won backing from a constellation of fringe players on the right who share little in common except for the fact that they have been ostracized by Republican insiders: Sarah Palin, the Party’s former Vice-Presidential nominee; Joe Arpaio, the anti-immigration sheriff from Arizona; and Jerry Falwell, Jr., the president of Liberty University, which was founded by his father, a leader of the religious right.

Trump is also at war with his Party’s more interventionist foreign-policy establishment, and he often attacks the biggest donors in the G.O.P., such as when he tweeted that Sheldon Adelson gave money to Marco Rubio, because “he feels he can mold him into his perfect little puppet.” In Iowa, Trump has started condemning Bob Vander Plaats, a Ted Cruz backer and leading power broker among evangelicals in the state.

Trump would undoubtedly welcome the support of any of the establishment figures he now ridicules. Like an inept high-school boy trying to win the affections of a girl, he sometimes seems to mock people in order to get their attention. (He eventually met personally with Adelson, and some establishment figures, like former Senator Bob Dole, have said that they would, at least, choose him over Cruz.) His slumming among what the journalist Rosie Gray has called the “alt right” is by necessity. Nobody has voted yet, and what looks now like an unstoppable movement may in a few weeks or months seem more like a passing fad. Still, this time, things may really be different. Trump, at the moment, rather than trying to ingratiate himself with the power brokers of his adopted Party, is trying to destroy them. What’s astonishing is that it’s working.