Democratic nominee Hillary Clinton won Wednesday night's final presidential debate, as she has won the two previous ones, but her Republican rival Donald Trump easily made the debate's headlines by his refusal to say if he would accept the election results if he lost.
As the bruising presidential campaign enters its final weeks, the sharp rivalry between the two candidates became visible when they declined to acknowledge each other at the beginning of the third and final debate in Las Vegas.
The key moment in the debate came near the end when moderator Chris Wallace challenged Trump to say whether he will accept the results of the November 8 election.
"I will look at it at the time. I'm not looking at anything now," Trump told Wallace. "I'll keep you in suspense."
In recent days, Trump has argued that the media, Hillary Clinton's campaign and election officials may be conspiring to rig the election against him.
"It was horrifying what he said," Clinton told reporters, "We are a country based on laws. And we've had hot, contested elections going back to the very beginning, but one of our hallmarks has always been that we accept the outcomes of our elections."
"He is denigrating...he's talking down our democracy," the former Secretary of State added.
According to a CNN/ORC instant poll of debate watchers, Clinton beat Trump 52 per cent to 39 per cent. There was a plus or minus 4 percentage point margin of error.
Trump did outperform expectations, however. Nearly six in 10 viewers said he did better than expected, whereas 44 per cent said the same of Clinton, the poll showed.
The showdown began with the two candidates -- Clinton dressed in an off-white signature pantsuit and Trump in a black suit with a contrasting bright red tie -- taking the stage at University of Nevada's Thomas and Mack Centre without a hand-shake or a smile.
The final clash provoked several flashpoints and moderator Chris Wallace had to ask the candidates not to talk over each other.
Trump repeatedly called Clinton "such a nasty woman", while the Democrat described him as "unfit" to be Commander in Chief of the US amed forces.
However, the evening focused more on policy than earlier showdowns and Trump looked intent on maintaining a more even manner.
Trump assured America that "nobody has more respect for women than I do" as he denied allegation of sexual assault as conspiracy or fiction.
The final debate was Trump's last and biggest chance to appeal to the women voters, many of whom have rejected him.
They debated over issues like Supreme Court; Second Amendment (protects the rights of people to keep and bear arms) where he hit Clinton for being anti-gun; abortion and the economy where the Manhattan billionaire boasted that as president, he would make the US an economic engine with annual growth rates of 5 or 6 per cent, while if Hillary goes to the White House, growth rates will be less than zero.
Trump went on to slam Clinton over her record as Secretary of State, the controversy over her private email server, and painting her as the symptom of a tired political establishment who had achieved nothing in her 30 years in public life.
The two rivals also clashed on immigration and the Islamic State during the 90-minute showdown.
With less than three weeks to go, it was the candidates' last chance to address their messages directly to the American people.
The debate ended, as it had begun, without the customary handshake in a sign of how hostile the campaign has become.
After the final answers ended, Clinton stepped away from the podium to thank the moderator while Trump stayed at his podium until she was out of reach.
The latest YouGov poll also declared Clinton the clear winner on Wednesday night. Out of 1,503 registered voters who tuned in to the debate, 49 per cent of participants said Ms Clinton came out on top. Thirty-nine per cent of voters argued that Mr Trump won the contest while 12 per cent claimed it was a tie.
Sixty-eight per cent of voters disagreed with Trump by suggesting that both candidates pledge to accept the final election results come November.
