US President Barack Obama launched a fight-back against Republican Mitt Romney in the second of three pre-election debates on Tuesday night.
Mr Obama - widely perceived to have lost their first encounter - came out swinging in New York on the economy, tax and foreign policy.
But the former Massachusetts governor hit back, accusing Mr Obama of broken promises and a record of failure.
The pair meet for a final pre-election debate in Florida on 22 October.
As he battles for a second term, the Democratic president has been clinging on to dwindling leads in the nine key swing states that are expected to decide the election on 6 November.
In the town hall-style forum at Hofstra University on Long Island, both men freely stalked the stage, circling, interrupting and at times heckling one another as they took questions from an audience of 80 undecided voters.
The moderator, CNN's Candy Crowley, often had to intervene to keep order between the rivals as each fought to make his point.
Mr Obama set the tone from his first answer, when he contrasted his own bailout of the US car industry with Mr Romney's position that auto-makers should have been allowed to go bankrupt.
The president forcefully accused Mr Romney of inconsistent positions, while claiming that his challenger could only offer a "one-point plan... to make sure the folks at the top play by a different set of rules".
Mr Romney meanwhile hammered away at the president's record on the economy, blaming him for unemployment of 20 million Americans and bloated federal deficits, while insisting the country could not afford another four years of Mr Obama.
"The president wants to do well, I understand," Mr Romney said. "But the policies he put in place have not let this economy take off as it could have.
"If the president were re-elected, we'd go to almost $20 trillion of national debt. This puts us on a road to Greece."
In one of the most scathing exchanges, the two bickered over last month's sacking of the US Libya consulate.
Mr Romney suggested the Obama administration may have attempted to mislead Americans over whether it was a terrorist attack.
But the president said it was "offensive" to suggest that he had played politics on an attack that claimed four Americans lives.
He countered that it was the Republican who had tried to turn a national tragedy to his advantage by releasing a partisan press release on the deadly assault.
Both candidates made impassioned pitches to America's middle class. Mr Obama said if America was serious about reducing the deficit, the wealthy would have to pay a little bit more.
"Governor Romney and his allies in Congress have held the 98% hostage because they want tax breaks for the 2%," said the president.
In his final answer he brought up Mr Romney's secretly recorded remarks at a fundraiser in May dismissing 47% of Americans as government-dependent tax avoiders who take no responsibility for their lives.
"When he said behind closed doors that 47% of the country considers themselves victims who refuse personal responsibility - think about who he was talking about," the president said.
'Binders full of women'
Mr Obama said voters had heard no specifics on Mr Romney's "sketchy" economic plan apart from eliminating Sesame Street's Big Bird and a family planning organisation that conservatives say promotes abortion.
But the Republican cited his experience balancing budgets in business, while running the 2002 Olympics and as governor of Massachusetts.
One of the few zingers of the encounter came when the pair clashed over former private equity chief Mr Romney's wealth.
Mr Romney was defending his investments in China through a blind trust when he asked Mr Obama if he had looked at his own pension. He said Mr Obama would find investments in China in his retirement plan, too.
"You know, I don't look at my pension," the president said. "It's not as big as yours."
Another fragment of the debate prompted a flurry of social media comment.
Arguing that he supports equal opportunities for women, Mr Romney said he once had "binders full of women" candidates for cabinet jobs when he was Massachusetts governor.
The third and final presidential debate is scheduled for 22 October in Boca Raton, Florida.