Obama Romney
US Republican presidential nominee Romney and US President Obama speak directly to each other during the second US presidential debate in Hempstead (Reuters)

Despite Republican candidate Mitt Romney holding his ground, US president Barack Obama emerged victorious from the second televised debate, with an extraordinary performance in stark contrast to the poor showing the President made at the first debate earlier this month.

Analysts agreed Obama, considered a gifted orator , came back in Hempstead, New York, where the debate was held, leaving his limp, grey-pale double back in Denver.

"The Alpha Male showed up tonight. In the second debate, President Barack Obama came. He saw. And he kicked butt," political commentator Paul Begala told the CNN.

"That low-key, low-energy President Obama whose performance was widely panned after the first presidential debate two weeks ago apparently stayed back in Denver," wrote Susan Page on USA today.

The White House duellist battled hard in the town hall-style format at Hofstra University, moderated by CNN presenter Candy Crowley and "circled around each other like tomcats in an alley," as New York Times journalist Alesasndra Stanley described.

Romney did repeat the good performance that won him great praises and possibly a surge of votes, earlier this month. However it wasn't enough against an Obama finally back to the land of the living.

"The Republican nominee absolutely had his moments in this debate. He was excellent when laying out the case for why we aren't better off than we were four years ago and for why his record as a jobs creator was far superior to President Obama's," Chris Cillizza wrote on the Washington Post, "but [...]these debates are about moments," and it was Obama to score the best ones.

"The President talked faster, pushed back harder and challenged Mitt Romney with more specifics in a crackling second encounter," Page wrote, "The Republican nominee often was put on the defensive."

"Thirteen days after he took presidential decorum to a Xanax extreme, he [Obama] tucked away a dinner of steak and potatoes and then went out on stage with plenty of red meat for anxious supporters," New York Times journalist Peter Baker said.

Obama appeared far more aggressive than two weeks ago, when he was accused of having been to polite and gentle towards his opponent, missing good chances to expose Romney's downsides and letting him walk out of the debate victorious undisturbed.

Democrats' supporters were relived, as Obama pointed out Romney's unlucky comment on 47 per cent of Americans who don't pay federal income taxes.

The president also scored two victory points with a stark remark on Romney's "bigger pension" and having the Republican candidate publicly contradicted by the moderator, when talking about Libya.

When Romney challenged over his pension, Obama countered: "I don't look at my pension; it's not as big as yours, so it doesn't take that long. I don't check it that often," provoking loud laughs from the public.

Then, as the former Massachusetts governor challenged Obama assertion that he called the attack on the US compound in Benghazi an act of terror the day after the US ambassador in Libya was killed, Obama called for the moderator Candy Crowley to check if that was true.

"He did [say it] in fact sir [...] He did call it an act of terror," Crowley said leaving Romney speechless for a second.

However it was Obama's performance as a whole that gained him analysts' praises.

"The President delivered a comeback performance that will stand as a model for future debaters of how to right a listing ship. This may have been the finest debate of his career and just at the moment when he needed it most," Alan Schroeder, a professor in the School of Journalism at Northeastern University, told CNN.

Romney's comment of "binders full of women" settled the final score.