NEW YORK (AP) — Even as he secured a commanding win in his home state of New York on Tuesday, Republican presidential candidate Donald Trump is continuing to shake up his campaign with new staff, new strategy and an overhauled campaign structure strikingly late in the game.

After several difficult weeks marked by a series of losses, Trump sounded confident Tuesday night as he predicted victories in upcoming states that would help him clinch the nomination ahead of his party's convention. But the win comes amid a serious campaign restructuring that has led to confusion about chains of command and less influential roles for Trump's previously insular inner circle.

Newly-hired campaign veteran Paul Manafort's role as convention manager has been growing behind the scenes.

"We're in a different phase of the campaign. And being in a different phase of the campaign requires different skills," Manafort told reporters after Trump delivered his victory speech in Manhattan. "We're in a phase where the end game requires winning smart, meaning we have to focus on not just winning the states, but what congressional districts we win and things like that. We're bringing that into the campaign."

Trump last month hired Manafort, a veteran of Republican conventions, to oversee his delegate strategy as he scrambles to lock down a majority of delegates by the end of June. The campaign also announced last week that Rick Wiley, who previously managed Wisconsin Gov. Scott Walker's campaign, had been hired as national political director, overseeing the campaign's field operations. The campaign is expected to announce additional hires soon.

"Not just me — he wants to bring on other people as well," Manafort said. "We're expanding the campaign. We're building a campaign that's got depth now, not just across the board."

But the shakeup hasn't been embraced by all. Trump's national field director, Stuart Jolly, tendered his resignation Monday — on the eve of New York's crucial presidential primary. The decision was met by disappointment among many of his campaign field staffers, who viewed the departure as a significant loss.

In a telephone interview with Fox News Tuesday morning, Trump insisted that everyone on his growing staff "seems to be getting along pretty well." But he also acknowledged the potential for bruised egos when asked how his loyal inner circle has responded to what Trump described as the addition of "very high-level people" to his team.

"When you bring other people in, I could see some people, their feelings get a little bit hurt," he said. "But frankly, you know, we're in a position where we'd like to see if we can close it out."

According to people familiar with the changes, Manafort has increasingly taken on a pivotal role and has been tasked with bringing on new people with more presidential campaign experience.

The changes have prompted questions about the role of Trump's longtime campaign manager Corey Lewandowski, who was front-and-center Tuesday night, chatting with reporters and embracing supporters after Trump's win was announced.

"We're growing, baby, we're growing!" he said when asked about his role.

Manafort also brushed aside suggestions that he had become the campaign's de-facto new manager. "We've divided the roles, we're working together, Donald Trump is our boss and we're very happy," he said.

But the tensions are clear. While Manafort stressed a new focus on policy, with new advisers on the way, Lewandowski downplayed Trump's plans to deliver a series of policy speeches.

"I don't think the voters really have as much concern, but I know you guys are dying for one," he told reporters.

Trump's eldest son, Donald Trump Jr., said earlier the changes were part of "a natural evolution in a process."

"I think we have to adapt, we have to start transitioning for the general," he told reporters Tuesday outside the midtown Manhattan polling center where he cast a ballot for his father.

"It's a very tactical change," he added. "And I think it's going to be very important in the campaign and the evolution of the campaign going forward."

Since Manafort began to assert his power, Trump's campaign has made a number of subtle but notable changes. He has been far more cautious on Twitter, has largely avoided controversy, and has spent less time on television, steering clear of the Sunday shows for two weeks running,

Manafort insisted that Trump alone was setting his own tone, however. "He's been growing on his own," he said.

Nonetheless, some things have remained the same.

Asked whether Lewandowski or Manafort was running the campaign, Trump Jr. said neither.

"My father. My father is always running it," he said.