The following evening at Trump Tower, the man who stepped out before the press — heralded by Sinatra’s “New York, New York” — to celebrate his 35-point victory in his home state’s primary appeared uncharacteristically subdued. He referred to his vanquished opponent not as “Lyin’ Ted” but as “Senator Cruz.” He held his usual grievances in check. After eight minutes, he departed the lectern without taking any questions.

Manafort had managed to impose a veneer of Beltway respectability on the campaign. More field organizers were now materializing in states like Pennsylvania, where local volunteers had hitherto been left largely to fend for themselves. Supporters who previously received no direction from the campaign before going on TV to expound on the candidate’s policies — “I just make [expletive] up,” Representative Duncan Hunter of California confessed to a Trump senior adviser — were now receiving daily talking points.

But the moment-to-moment decision-making — where to go, whom to see, what to say and how to say it — still rested almost exclusively upon the whims of Trump and, secondarily, with the person in his immediate proximity, who was almost always Lewandowski. That became apparent to me on the morning of April 25, the day before the string of Northeastern primaries that would restore Trump’s indomitability. The candidate was seated in the front of his Citation as it departed the airstrip of Warwick, R.I. — a stop that, Manafort and Lewandowski agreed, had been a complete waste of the candidate’s time, given that he was ahead of Cruz there by 40 points. But when Trump told Lewandowski, “I can’t just not go there,” there was little point arguing. Lewandowski began making calls to his advance team on Sunday morning. Some 24 hours later, Trump walked into a sweaty and delirious tented gathering adjacent to a Warwick hotel — exulting, with customary hyperbole: “We set this up 12 hours ago! There’s thousands outside — we need a bigger tent!”

Later that day, en route to West Chester, Pa., Trump’s thoughts kept wandering afield from politics. He sat with a large stack of newspaper clippings — some of them with handwritten notes from his daughter Ivanka — at his feet. To his right sat his 32-year-old son Eric, whom I heard Trump refer to as “honey.” He perused some documents relating to a land deal he was considering, pausing to fret over the fate of his friend Tom Brady, the New England Patriots quarterback whose four-game suspension for his role in the Deflategate scandal was upheld that morning by a federal appeals court: “He should’ve sued the N.F.L. in Boston at the very beginning.” He asked Lewandowski whether his campaign schedule would allow him to attend the June 25 grand opening of his Turnberry golf resort on the coast of Scotland.

“If we get to 1,237, you’re there,” Lewandowski said. “If we’re at 1,100, you’re going nowhere.” Trump scowled a bit but did not protest. I was reminded that Trump was still fundamentally a real estate developer with exactly zero previous campaign experience, who had gotten this far by spending only a fraction of what his opponents had and against the wishes of his party — who was as new to the idea of a Trump candidacy as the rest of us were.

Although his political maturation over the past year had not been altogether linear, it seemed clear that an understanding of what his candidacy meant to his supporters was taking root. Trump seemed aware, despite his insistence that voters of all stripes were drawn to him, that his constituency came chiefly from white working-class Americans who felt left out of the Obama recovery and cheated by what they saw as a rigged economic system. Playing to this sentiment, he had begun to include in his speeches a litany of dire economic statistics pertaining to whichever state he happened to be visiting at the time. The data, compiled by Sam Clovis and Stephen Miller, senior policy advisers, invariably cited the collapse of that local manufacturing sector over the past two decades. It had become axiomatic in Trump World that wherever jobs had been lost was also where Trump’s voters could be found. “They’re great people,” he murmured back on the plane after the event in Buffalo. “And they want help.” His face crinkled in disgust. “They don’t want hope. They want help.”

It was a sobering reminder of the expectations that a President Trump might find on his shoulders come January. But the moment passed, and his mood seemed to regain altitude, the desperate souls on the rope line reaggregating into an adoring mass of victory-assuring, superlative-defying yugeness. “So you’ve covered other people — nobody comes close to this,” he said. “Two guys from Fox said they’ve never seen anything like it.”

We rose upward through the skies in the vehicle Trump referred to as “just about the fastest plane made,” eventually passing over the Ferry Point golf course that Trump said he had built faster than anyone else could, and finally toward the great Manhattan skyline that Trump had made even greater — a taste of what he could do for America, if its great people would only let him.