The competitors for the White House have faced off in what could have been the most-watched presidential debate in US history.
A record 100 million people were expected to watch the first debate between Republican Donald Trump and Democrat Hillary Clinton, televised from in New York.
The stakes were high as the candidates headed into the debate tied in most national polls before the November 8 election.
The first topic discussed was job creation, with the candidates being asked how they would make American manufacturers bring back production to the US.
The debate heated up as the rivals discussed the NAFTA trade deal.
Off topic while still debating under the banner "Achieving Prosperity", Trump mocked Clinton for spelling out on her website how she would fight ISIL.
"At least I have a plan," Clinton countered.
The candidates also hit out at each other over issues that have plagued their campaigns: for Trump, his refusal to release his tax returns, and for Clinton, controversy over the use of a private email server during her time as secretary of state.
Trump said as soon as Clinton releases 33,000 emails, "I will release my tax returns".
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Moving on to the second topic of the night, "America's Direction", and how to heal America's racial divide, Clinton said "race still determines how people are treated in the US criminal justice system".
The issue has caused heated debate in the United States and was again put in the spotlight last week after deadly police shootings of black men in Charlotte and Tulsa.
Trump used his opening segment on the same issue to stress the importance of "law and order", and praised the stop-and-frisk policy - which was struck down by a New York judge and widely deemed a form or racial profiling.
Later on, Clinton said Trump has a "long history of engaging in racist behaviour", bringing up how his family company was sued by the justice department for racial discrimination in 1973 for not renting apartments in one of its developments to African Americans.
Trump responded that the lawsuits had been settled "with no admission of guilt".
When he was pressed about what he would say to people offended by his years of questioning whether President Barack Obama was born in the US, Trump did not respond directly, instead
When he was pressed about what he would say to people offended by his years of questioning whether President Barack Obama was born in the US, Trump did not respond directly, instead praising himself for forcing Obama to produce his birth certificate.
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The third topic chosen by the Presidential Debate Commission for Monday's showdown at Hofstra University was "Securing America".
Getting back to discussing the fight against the Islamic State of Iraq and the Levant (ISIL, or ISIS) and clashing with Clinton over the Iraq War, Trump said "we should have taken the oil". He went on to say that if that had happened, ISIL would not have been able to form as oil is a main source of income for the group, which has taken territory in Syria and Iraq.
Trump, known for fiery statements on the campaign trail, later stated that he has "a winning temperament", leading Clinton to give off a big smile before discussing the US-Iran nuclear deal.
She scored laughter from the audience as she said Trump was too easily provoked to serve as commander- in-chief.
"A man who can be provoked by a tweet should not have his fingers anywhere near the nuclear codes," she said.
Trump's popularity had been rising in the run-up to the debate.
Quinnipiac University declared the race "too close to call" on Monday, with its latest national poll of likely voters suggesting 47 percent support for Clinton and 46 percent for Trump.
"It really felt great," Trump told reporters after the debate.
But political analyst Jason Johnson told Al Jazeera that he would not be surprised "if we see slight chances in the polls at the end of the week " in favour of Clinton.
"Trump came out aggressively ... but never offered much in terms of substance or answers," he said.
"I think Hillary did what she needed to do better than Trump. She offered solutions ... explained how she sees America and her worldview. Her supporters will come out very enthusiastic."
It was the first time the two candidates stood side by side since becoming their parties' nominees.
Two more debates are to follow on October 9 and October 19.
Source: Al Jazeera News