Donald Trump’s upset victory over Hillary Clinton in the presidential race stunned the political establishment and the pollsters – but his campaign manager credited the phenomenon of “undercover Trump voters” and several other key factors Wednesday morning for their win.

Kellyanne Conway, speaking with “Fox & Friends,” said there was a “small but potent” force all along who didn’t reveal they planned to vote for the Republican nominee.

“It’s not that they’re embarrassed,” she said, but that they were “tired of arguing” about their political preference. The "undercover" voters followed a similar pattern displayed by so-called "shy voters" who backed the "Brexit" vote in the U.K. over the summer.

Conway said their voters fell into a range of categories, including Hispanic voters, women, union members and other constituencies that traditionally vote Democratic.

The common thread among these voters, she said, was they wanted the country taken in a “new and different direction,” they had an unfavorable view of Clinton and they shared certain concerns – about everything from ObamaCare premium increases to the decline of manufacturing jobs to the threat of terrorism.

Further, she said, “Candidates matter. There’s no substitute for a great candidate.”

Clinton, who did not speak publicly Tuesday night, plans to address supporters Wednesday morning in New York City.

The depth of the divide between the predictions and the outcome in Tuesday’s election will be studied for years. But in terms of the on-the-ground strategy, Conway noted that the campaign committed itself to winning Pennsylvania after seeing their message fit with the beliefs of so many people in the state.

While almost every poll showed Trump losing the state, the campaign devoted money and resources and attention to the battleground for weeks.

“He was never leading in Pennsylvania, not one time,” she said.

But after the campaign won what Conway called their “core four” – Iowa, Ohio, Florida and North Carolina – they knew they could win by flipping one more state.

As it turned out, the victory in Pennsylvania put them over the top early Wednesday morning.

Clinton won her share of battlegrounds, including Virginia and Nevada and Colorado, but could not make up for Trump’s strong performance in other states thought to favor the Democrat.

Speaking to cheering supporters early Wednesday morning at his victory party in New York City, the Republican candidate and now president-elect said Clinton called to congratulate him, and Fox News confirms she conceded. Despite their hard-fought campaign, Trump praised Clinton for her service and said “it is time for us to come together as one united people.”

“I will be president for all Americans,” Trump vowed, after a brief introduction by running mate Mike Pence.

Sounding a call to “reclaim our country’s destiny,” Trump declared: “The forgotten men and women of our country will be forgotten no longer. … America will no longer settle for anything less than the best.”

Though Clinton called Trump, her campaign initially did not concede defeat. Earlier, her campaign chairman John Podesta addressed supporters nearby in New York and said several states were “too close to call.”

Clinton herself did not appear at the rally. Podesta had urged supporters to “head home” and said they would not have “anything more to say tonight.”

Amid Trump’s victory, Republicans also were projected to hold onto their majority in the House and Senate, improving Trump’s chances of advancing his agenda in office.