WASHINGTON -- Donald Trump has urged Americans to "come together as one united people" after winning a historic U.S. presidential election over Democratic candidate Hillary Clinton, who conceded defeat and said the nation should give Trump a "chance to lead."
Billionaire Republican nominee Trump said in his victory speech to supporters at his headquarters in a Manhattan hotel ballroom in the early hours of November 9 that he would be a president "for all Americans" and would "not let you down."
Trump said he had spoken by phone to Clinton, who had conceded the election. Clinton, who was on pace to win the nationwide popular vote despite losing the Electoral College, did not address her supporters on election night but delivered a concession speech to her campaign staff and backers in New York shortly before noon on November 9.
In the speech, her first public remarks since her stunning loss, the Democratic candidate said she spoke to Trump following the November 8 election and "offered to work with him on behalf of our country."
"We owe him an open mind and the chance to lead," Clinton said, adding that the peaceful transition of power was critical to U.S. democracy.
"We have seen that our nation is more deeply divided than we thought," she said. "But I still believe in America, and I always will. And if you do, then we must accept this result and then look to the future."
WATCH: Defeated Democratic nominee Hillary Clinton called on her supporters to keep an open mind about Donald Trump, and give him a chance to lead the country. (AP)
Most opinion polls ahead of the election showed the former U.S. first lady, senator, and secretary of state likely to defeat Trump, a billionaire real estate mogul and former reality TV star who has never held elected office.
Clinton, 69, and Trump, 70, had savaged one another throughout a campaign that some historians described as having a level of mudslinging and overheated rhetoric unprecedented in modern U.S. history.
But in his victory speech, the president-elect, who at one point in the campaign had suggested Clinton would go to jail for her controversial handling of e-mails as secretary of state, praised his rival for her dedication and service to the nation.
"Hillary has worked very long and very hard over a long period of time, and we owe her a major debt of gratitude for her service to our country," he told his jubilant supporters. "I mean that very sincerely."
U.S. President Barack Obama delivered his first public remarks on the election following Clinton's address, saying in Washington that he called Trump early on November 9 to congratulate and invited him to come to the White House the next day to discuss the transition.
Obama said he had instructed his staff to work as hard as possible to ensure a smooth and successful transition of power when Trump is inaugurated as the 45th president of the United States on January 20.
"The peaceful transition of power is one of the hallmarks of our democracy and over the next few months, we are going to show that to the world," he said, speaking outside the White House.
WATCH: U.S. President Barack Obama promised there would be a smooth transition of power between his administration and that of President-elect Donald Trump. (AP)
Electoral College Vs. Popular Vote
Trump sealed his victory when he was declared the winner in Wisconsin, giving him 276 electoral votes and taking him past the 270 needed to win the election.
Clinton had wins in big states like California, New York, Illinois, and much of the northeast, but she could not overcome surpirse defeats in the Midwestern states of Pennsylvania and Wisconsin, which often go to the Democratic candidate in presidential elections.
Trump was nearing 300 electoral votes in the afternoon on November 9, though counting in a handful of states continued.
But Clinton was on track to win the popular vote, having captured 47.7 percent compared to 47.5 percent to Trump with almost 125 million votes counted, according to a nearly complete vote count on November 9.
If Clinton holds her nationwide lead, which was at around 236,000 votes, she would become the second U.S. presidential candidate in the last five elections to win the popular vote but lose the White House to an opponent who triumphed in the tally because of the mostly winner-take-all, state-by-state Electoral College.
It is rare but not unprecedented for a candidate to win the required number of Electoral College votes (270) but lose the popular vote, last occurring when Republican George W. Bush beat Democrat Al Gore in 2000.
Exit surveys conducted around the country on Election Day by the AP and the main U.S. TV networks showed more than half of voters cast their ballots with reservations about their candidate or because they disliked the others running.
Trump captured the Republican nomination vowing to upend politics-as-usual in Washington and pushing controversial proposals like "extreme vetting" of Muslims who want to enter the country and building a wall on the southern border to keep out immigrants from Central America.
Clinton had pledged to build on the legacy of outgoing President Obama and touted her decades of public service as qualifying her to lead the nation. She was seeking to become the first female U.S. president.
In her concession speech, Clinton acknowledged that she had not "shattered that highest and hardest glass ceiling" and told "all the little girls" watching: "Never doubt that you are valuable and powerful and deserving of every opportunity in the world and chance to pursue your dreams."
VIDEO PROFILE: Donald Trump, America's Next President
Mixed Reactions Globally
Trump's victory triggered a mix of reactions from around the globe amid questions about how the political newcomer, whose campaign platform tilted toward isolationism, will run the country and what Washington's role in the world will be under his administration.
The European Union sounded a cautious note, with EU foreign-policy chief Federica Mogherini saying that Washington and Brussels "will continue to work together" and rediscover "the strength of Europe."
"EU-U.S. ties are deeper than any change in politics," Mogherini wrote on Twitter.
German Chancellor Angela Merkel offered Trump "close cooperation" on the basis of shared transatlantic values such as "democracy, freedom, respecting the rule of law, people's dignity regardless of their origin, the color of their skin, religion, gender, sexual orientation, or political views."
The Kremlin, meanwhile, expressed optimism that Trump's victory could repair U.S.-Russian ties that have been battered over Russia's actions in Ukraine -- including the seizure and illegal annexation of Ukraine's Crimean Peninsula -- and over Russia's military support for Syrian President Bashar al-Assad's regime.
President Vladimir Putin, for whom Trump expressed admiration during the election campaign, congratulated Trump on his election in a telegram early on November 9.
"It is not an easy path but we are ready to do our part and do everything to return Russian and American relations to a stable path of development," Putin said.
Ukrainian President Petro Poroshenko said he hoped Washington would continue to support Ukraine in its standoff with Russia.
With reporting by AP, NBC, The New York Times, AFP, and Reuters