On the eve of their first presidential debate, President Obama leads or is at parity with Mitt Romney on virtually every major issue and attribute in what remains a competitive general election, according to a new Washington Post-ABC News poll.

The new survey also highlights an emerging dynamic: the disparity between the state of the race nationally and in battleground states, where campaigning and advertising by the two candidates have been most intense and where the election will be decided.

Nationally, the race is unmoved from early September, with 49 percent of likely voters saying they would vote for Obama if the election were held today and 47 percent saying they would vote for Romney. Among all registered voters, Obama is up by a slim five percentage points, nearly identical to his margin in a poll two weeks ago.

But 52 percent of likely voters across swing states side with Obama and 41 percent with Romney in the new national poll, paralleling Obama’s advantages in recent Washington Post polls in Florida, Ohio and Virginia.

Obama and Romney have focused outsize efforts in swing states: About a third of all voters in these states say they’ve heard from each side. Outreach makes a particularly big difference among less-reliable young voters, who proved critical in electing Obama four years ago.

Public opinion ahead of first debate

Romney enters Wednesday’s debate in Denver under acute pressure to turn around a campaign that has lost ground in states — particularly Florida and Ohio — widely seen as critical to his prospects.

“He’s had a tough couple of weeks, let’s be honest,” New Jersey Gov. Chris Christie (R) said of his party’s presidential contender in a Sunday interview on CBS’s “Face the Nation.” “He’s going to come in Wednesday night, he’s going to lay out his vision for America . . . and this whole race is going to turn upside down come Thursday morning.”

By a wide margin, voters expect the president to win the debate matchup, and the new survey points to key obstacles remaining in Romney’s way. But there are also signs that some parts of the political landscape have shifted somewhat in favor of the Republican.

A slim majority of voters now see Romney’s wealth as a positive, signifying his achieving the “American Dream.” Fewer are focusing on issues of economic inequality and the gap between rich and poor. And there has been a big jump in the number of voters who say he has paid his fair share in taxes.

Just after Romney released his 2010 tax return earlier this year that showed he had paid a federal income tax rate of about 14 percent, 66 percent of voters said he had not paid his fair share. Now, after the release of his 2011 return showing a similar tax rate, 48 percent say he is not paying his fair share, and about as many, 46 percent, say he is.

Romney still faces challenges on this terrain. As was the case before the nominating conventions, almost six in 10 voters say that as president, the former Massachusetts governor would do more to favor the wealthy than the middle class. And by 57 percent to 39 percent, most voters say it is fair that some Americans — including senior citizens on Social Security, people on disability and the working poor — do not pay federal income taxes.

Romney’s description of the “47 percent” of Americans who pay no income taxes as people who consider themselves “victims” has stirred controversy and served as fodder for a tough new ad from the Obama campaign. He made the remark in a secretly recorded video from a springtime fundraiser.

While Romney loses that argument in the current poll, an anti-government message has a deep vein of support. More than seven in 10 are dissatisfied or angry with the way the federal government is working, and by 51 percent to 43 percent, voters see government programs as doing more to create dependency among the poor than to help them get back on their feet.

Moreover, Romney and his running mate, Rep. Paul Ryan (Wis.), may be making headway in their argument about the threat of government overreach. Asked whether overregulation or a system that favors the wealthy is the bigger problem, 49 percent of voters say unfairness and 42 percent say overregulation. This is the first time in polls this year that under 50 percent of voters chose unfairness as the larger concern.

Similarly, the percentage of voters who say the government should pursue policies aimed at narrowing the gap between rich and poor has also dipped, although a slim majority, 52 percent, still support such efforts.

Obama continues to hold double-digit advantages when it comes to being the more friendly and likable of the two, and as the candidate more voters trust on social issues, women’s issues and terrorism. He maintains a big lead when it comes to empathizing with people facing economic problems. And he has a 10-point edge when it comes to handling “an unexpected major crisis,” the first time the question has been asked this year.

He and Romney are judged more evenly on some other key issues, including the deficit, health care and Medicare. Romney does not have significant leads in any of the areas tested in the poll, but he has a numerical edge on dealing with the federal budget deficit, 48 percent to 45 percent, among all voters.

On the economy — still the dominant issue in the campaign — voters render a split verdict, with the two tied at 47 percent.

The state of the economy and dissatisfaction over the country’s direction continue to be steep obstacles to the president’s reelection — but Obama benefits from recent improvements in voters’ moods, even if it is mainly Democrats who are feeling better about things.

More voters still give Obama negative ratings for his handling of the economy, but the number of approvers has edged up to 47 percent, its highest level in nearly two years.

The president’s overall approval rating among registered voters is now 49 percent positive, 49 percent negative. He tilts positive among all Americans, with 50 percent approving of his job performance and 46 percent disapproving.

Voters are also split on Obama’s handling of international affairs. This comes at a time when the administration has been on the defensive over the Sept. 11 attack in Libya that killed four Americans, including U.S. Ambassador J. Christopher Stevens.

The president gets higher marks when it comes to voters’ assessments of his knowledge of world affairs: Sixty-four percent say he knows enough to be effective. At this stage, voters are less convinced about Romney: Fifty-one percent perceive that he has sufficient knowledge of international affairs to be an effective president; 43 percent say he does not.

There is more parity in voter expectations for what will happen with the economy after the election: Few voters are “very confident” that the economy will get back on track in the next year or two, regardless of who wins. Things have seesawed in a positive direction here for Romney: Fifty-one percent of voters are at least somewhat confident that things would quickly improve under his administration, up five points from before the conventions.

Peyton M. Craighill and Scott Clement contributed to this report.