Romney ripped the president's record on the economy with a tone calculated to convey more sorrow than anger. He told the stories of individuals who have come up to him and his wife, Ann, at campaign events asking for help in getting a job or saving their home from foreclosure.
"Yes, we can help," he said, looking straight into the camera, speaking to the millions of voters watching from their homes, not the hundreds of them in the University of Denver arena. "But it's going to take a different path, not the one we've been on."
Obama, who seemed a bit stiff at the beginning, warmed up as he hammered Romney for a tax proposal he said didn't add up and defended the Affordable Care Act for its most popular provisions, including protecting those with pre-existing medical conditions.
The two men laid out fundamentally different visions for the role of government and the nation's path to prosperity.
"Free market and free enterprise are more effective in bringing down costs than anything," Romney said in the discussion of health care. "The private market and individual responsibility always works best."
Obama talked about the responsibilities of citizens to one another and described spending on education and other programs as an investment that in the end spurs growth and jobs. "The federal government can't do it all, but it can make a difference," he said in an exchange in which he extolled Abraham Lincoln.
There didn't seem to be an embarrassing gaffe or a single sharp exchange that defined the evening.
Romney again and again reminded voters of their economic woes and blamed Obama's policies for contribution to slow job growth, increasing poverty, home foreclosures. He questioned Obama's economic competence. "I've been in business 25 years," he said at one point. "I have no idea what you're talking about."
And Obama again and again raised questions about whether Romney's numbers added up and whether his policies would work, saying his tax proposals would explode the deficit and benefit the wealthy. When Romney disputed that saying he wouldn't reduce the tax burden on the wealthy or approve tax cuts that increased the deficit the president expressed incredulity.
"Now four weeks before the election, he is saying his big, bold plan is: Never mind," Obama said. He accused Romney of proposing to "double down" on economic policies that contributed to the economic meltdown that greeted him four years ago in the Oval Office.
In other words, Romney cast the election as a referendum on Obama's first term in office. Obama cast it as a choice between his plans and those of his opponent.
Much of the discussion was a festival for fact-checkers, a dizzying competition of numbers on tax policy, on spending levels, on the costs of the proposals each has made, on Romney's record as governor of Massachusetts and Obama's record as president.
But Romney showed the value of the 19 debates he participated in during the GOP primaries and the extended practice sessions he has scheduled in recent weeks. He seemed relaxed and conversational, giving no quarter when challenged by the president.
Obama, in contrast, hadn't debated since the last of his three encounters with John McCain four years ago. Not since then has he faced an opponent on a level playing field the podium in front of him not even adorned with the presidential seal. At times, he looked annoyed at being challenged and at having his record depicted in the most negative terms.
After Obama vowed to reduce the federal budget deficit in his second term, Romney told him: "You've been president four years."
One small sign that indicated which side was more eager to discuss the face-off: Republican surrogates flooded the "spin room" to tell reporters afterward their candidate had prevailed. Democratic surrogates didn't show up until precious minutes later.
Since the Democratic National Convention last month, polls show Obama has opened a narrow lead nationwide and a bigger one in such swing states as Ohio and New Hampshire. Romney has been forced to do damage control over release of a secretly recorded video of him telling a Florida fundraiser that 47 percent of Americans were dependent on government, think they are victims, and that it was "not his job" to worry about them.
If Obama could be satisfied with a draw, Romney went into the race needing to shake things up.
As with every presidential debate, the two candidates were poised to seize on a sharp exchange, the memorable quip or the opponent's gaffe that could lead the news accounts afterward and define the evening for voters. Still, for this particular debate, there was also the possibility of exploring the considerable differences between the candidates on how they would spur growth and their views on the role of government in the 21st century.
Even though the two sides effectively have been campaigning against one another for most of the year, the vast majority of ads have been negative and the points of attack often an ill-considered comment by the other guy, sometimes taken out of context from Obama's "you didn't build that" to Romney's "I like to fire people."
The candidates and their running mates continue to provide fuel for those fires. The latest: Vice President Biden's comment at a rally this week that the middle class has been "buried" by economic woes for the past four years. (That would be during Obama's first term.)
But the length of the debate, the relatively unstructured format and the focus on four broad topics were designed to encourage a substantive discussion with varying degrees of success.
For 90 minutes, standing side by side, the two contenders were slated to discuss various aspects of the economy for 45 minutes, then health care, governing and the role of government for 15 minutes each.
The ideological divide between Obama and Romney on dominant questions of the day this year, it's the economy and its slow climb out of recession is as wide as it has been in any presidential election in more than a generation. That gulf was apparent in the discussion of issues from health care to the deficit to tax policy.
That was a point both men referred to in their closing statements. "Four years ago, we were going through a major crisis," Obama said. "The question now is, How do we build on those strengths?"
Romney, who got the last word, said a second Obama term would lead to more economic problems. He said the candidates offered "two very different paths," adding, "They lead in very different directions."