Republican Mitt Romney delivered a strong performance in his first presidential debate, putting a more passive Barack Obama on the back foot as he reignited hope for his flagging campaign.Needing a good showing to turn around poor poll numbers, the former Massachusetts governor went on the offensive Wednesday, hammering the president for economic policies he said had "crushed” America’s middle class.Romney played the aggressor throughout the 90-minute encounter and appeared far more at ease in the cut-and-thrust of the debate format, which left Obama seeming at times nervous and irritated, at others under-prepared.Obama did jump on Romney’s lack of specifics as the rivals clashed on taxes and health care reform, but the president stuttered through several of his more detailed answers, while his Republican opponent was crisper and clearer."The president has a view very similar to the view he had when he ran four years ago: that a bigger government, spending more, taxing more, regulating more -- if you will trickle-down government -- would work,” Romney said."That’s not the right answer for America. I’ll restore the vitality that gets America working again,” he vowed. "Middle-income families are being crushed, and the question is, how to get them going again.”Obama hit back by suggesting Romney would bring $5.4 trillion in tax cuts geared towards the wealthy, and said his Republican foe hadn’t been clear on which tax loopholes he would close in order to maintain revenue."Governor Romney has a perspective that says if we cut taxes skewed toward the wealthy and cut back regulations, we’ll be better off. I have a different view,” the Democratic incumbent said, calling for "economic patriotism.”Romney challenged Obama’s claims as the tax issue sparked what proved the fiercest clashes in a mainly low-key televised debate watched live by tens of millions of Americans."Virtually everything he said about my tax plan is inaccurate,” Romney said. "If the tax plan he described were a tax plan I was asked to support, I would say absolutely not.”Obama clings to a narrow lead in his bid to defy the omens of a stubbornly sluggish economic recovery and to become only the second Democrat since World War II to win a second term.Romney, down in almost all the key battleground states that will decide who gets the 270 electoral votes needed to win on November 6, sought a sharp change of momentum."I don’t think there’s any doubt that Romney won,” Terry Madonna, director of the Center for Politics and Public Affairs at Franklin and Marshall College, told AFP."He was more aggressive without being pugnacious or provocative or combative. The president seemed a bit flat. He seemed, I wouldn’t say annoyed at times, but almost disconnected, almost not comfortable.”The Romney campaign hailed a clear win for their man. "If this was a boxing match, it would have been called an hour into the fight,” said top political adviser Eric Fehrnstrom.AFP