Hillary Clinton, hopeful Tuesday that she was poised to shatter the nation's "highest and hardest glass ceiling," instead Wednesday publicly conceded the presidential race to Donald Trump, saying the nation owed "him an open mind and the chance to lead."

“I hope that he will be a successful president for all Americans," Clinton told supporters, including her staff, as she tried to strike a hopeful note despite what she described as a "painful" loss.

“I still believe in American, and I always will," Clinton said, surrounded by her family, including former president Bill Clinton.

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In introducing his running mate, Virginia Sen. Tim Kaine said Clinton “has been and is a great history maker."

Several hours earlier, Clinton called Trump, to congratulate him on becoming the nation's president-elect. However, she did not make an appearance before backers gathered at the Jacob K. Javits Convention Center for what was expected to be a victory party.

Instead, her campaign chairman, John Podesta, made brief remarks. “It’s been a long night, and it’s been a long campaign, but I can say we can wait a little longer," he told Clinton's despondent supporters.

Outside the New Yorker hotel in Manhattan, where Clinton would deliver her concession remarks, disappointed supporters, many still wearing their guest badges from the previous night's campaign event, tried to get in to see their defeated candidate.

Anita Broccolino said she wanted to get into the event "to show support for Hillary, to show her we love her."

It appeared that, despite her loss, Clinton may win the national popular vote, which would be only the second time in recent history that a candidate had done do while losing the election (Al Gore also did so in 2000 in his loss to George W. Bush).

It is a shock to the Clinton team after most major polls showed her with a comfortable lead in all of the major battleground state, including Pennsylvania and Michigan, two blue-leaning states that are critical, particularly for Democrats. Prior to Trump's win there, a Republican hadn't won Pennsylvania since 1988.

A few weeks ago, Clinton's lead was even more pronounced. Following the third debate in Las Vegas, in which Trump called Clinton a "nasty woman" and said he might not honor the outcome of the election, an ABC News tracking poll showed Clinton leading the GOP nominee by 11 points.

Later in the month, FBI Director James Comey announced that his agency was reviewing new emails that might be relevant to its investigation of her private email server, but just two days before the election, Comeysaid the emails were either duplicates or not germane and that he was making no change in his previous recommendation against criminal charges.

Still, the move revived the one issue that had proved most damaging to Clinton's candidacy — and her poll numbers began to reflect it.

Additionally, news organizations, including Fox News, falsely reported that she would be indicted in a separate investigation related to her family's charitable foundation.

Clinton responded on the campaign trail by shifting her message to take aim at Trump, even warning at several rallies that the real estate mogul's temperament risked a global nuclear war. On the eve of the election, Clinton told supporters in Grand Rapids, Mich., that there was no veto over a presidential decision to launch a nuclear weapon and that it takes just four minutes to launch one.

Democrats will now begin a long process of soul searching. During the heat of the campaign, they had remained optimistic that a number of the setbacks they'd encountered, including the WikiLeaks email hack linked to Russia, were survivable.

They were wrong.

Contributing: Eliza Collins in New York