WASHINGTON — Republican Mitt Romney entered Monday night's debate on foreign policy with the goal of presenting himself as a competent, plausible alternative to President Barack Obama as commander in chief.

But Romney appeared to cede many positions to Obama, moving closer to the president on a range of issues and presenting them in a softer way.

His strategy was clear from the opening question, when he passed up a chance to criticize Obama for his response to the attack on the U.S. diplomatic mission in Benghazi, Libya. He went on to praise Obama for overseeing the killing of Osama bin Laden and ruled out a U.S. military role in Syria's civil war, as Obama has done.

"I'm glad that Governor Romney agrees with the steps that we're taking," Obama said at one point. "There have been times, Governor, frankly, during the course of this campaign, where it sounded like you thought that you'd do the same things we did, but you'd say them louder and somehow that would make a difference."

Instead of offering a different view of the United States' role in the world, Romney mostly sought to distinguish himself from the president by turning a foreign policy debate into one about domestic issues.

Not long into the 90-minute debate, Romney seized on an opening Obama gave him to talk about the American economy, a subject he returned to repeatedly throughout the debate, including in his closing statement.

That tack became evident after an early exchange on the Middle East that highlighted Obama's command of the issue and Romney's relative uncertainty when talking about international affairs.

Incumbent presidents often hold an edge on foreign policy questions, few more so than Obama, whose signature credential is approving the May 2011 mission that killed bin Laden. That success helped eliminate, at least until recently, the historical advantage Republicans have had over Democrats on issues of national security.

But recent polls have shown Obama's advantage dwindling. The fact that foreign policy has become a potential vulnerability for Obama illustrates just how much ground Romney, who stumbled badly through his trip to Europe and Israel this summer, has gained since the first debate earlier this month.

A Washington Post-ABC News tracking poll released hours before Monday's debate showed that Obama no longer holds a clear advantage on who likely voters believe would better manage international affairs. The eight-point advantage Obama held in September has shrunk to three points, according to the tracking poll.

The survey also showed that nearly as many likely voters believe Romney would be a better commander in chief than the president, the critical question the challenger had to answer for voters Monday night.

A CBS News instant poll after the debate found that 53 percent of respondents believed Obama won it, with 23 percent saying Romney did and the rest calling it a tie.

Nonetheless, each side will probably see positive elements in their candidates' performance as each campaign sets off immediately for the half-dozen or so swing states that will decide the election.

Without any glaring missteps Monday by either candidate, the three presidential debates appeared to help Romney, injecting a vital burst of energy into his campaign after a lackluster summer for the challenger.

His aggressive performance in the first debate in Denver contrasted sharply with Obama's listlessness, and Romney largely held his own nearly two weeks later in the town-hall-style forum in Hempstead, N.Y.

Obama on Monday was harsh, even condescending at times, toward Romney, a former governor of Massachusetts with no foreign policy record of his own.

Responding to Romney early in the debate, Obama noted that he understood his rival had "never executed foreign policy."

He later explained, as if to a child, that the modern American navy has aircraft carriers "where planes land on them" and "ships that go underwater, nuclear submarines," to rebut Romney's criticism that federal spending cuts threaten to reduce U.S. naval power to levels not seen since early in the last century.

Romney used his last appearance with Obama to argue broadly that the president has left the nation weaker abroad than it was when he took office, in part by mishandling the economy and fiscal matters at home.

He accused Obama of unsettling traditional allies such as Israel, failing to effectively guide the Middle East uprisings known collectively as the Arab Spring, and leaving unchecked Iran's nuclear program - one of several foreign policy problems the president inherited from the previous administration.

"We're four years closer to a nuclear Iran," Romney said, twice in a row.

Obama raised several pointed questions of his own about whether a Romney presidency would mean new wars - accompanied by swelling budget deficits - for a country tired of them after more than a decade of conflict.

"Part of American leadership is making sure that we're doing nation-building here at home," Obama said. "That will help us maintain the kind of American leadership that we need."

Romney's most recent criticism of Obama's foreign policy record has focused on the administration's confusing account of the Sept. 11 attack in Libya that killed Ambassador Christopher Stevens and three other Americans.

Heading into this debate, though, Romney had made several missteps in attacking Obama on the specifics of the Benghazi attack. First among them was his decision to issue a statement within hours of the assault suggesting that Obama is more interested in cultivating goodwill in the Middle East than in protecting U.S. diplomats.

Offered the chance Monday to criticize Obama again on the issue, Romney instead turned the question to one about the need to fight Islamist extremism in the Middle East.

"I'm glad that you recognize that al-Qaida is a threat, because a few months ago when you were asked what's the biggest geopolitical threat facing America, you said Russia, not al-Qaida," Obama said in a typically sharp response. "You said Russia. In the 1980s, they're now calling to ask for their foreign policy back because, you know, the Cold War's been over for 20 years."

Even in areas where there have been differences, the candidates largely coalesced Monday around policies that Obama is already pursuing.

Those included exchanges over how best to help Syrian rebels topple President Bashar Assad in a worsening civil war, to confront China over its trade policies, and to encourage Israel to more actively pursue peace with the Palestinians.

Obama has opposed arming Syria's little-known rebel groups, worried that heavy weapons would exacerbate a conflict already spilling its borders. He has sent logistical and humanitarian aid instead.

"What we can't do is suggest that giving heavy weapons to the Syrian opposition is a simple proposition that will make us safer in the long run," Obama said.

Romney has advocated sending weapons, and on Monday he said affecting the outcome in Syria offers the United States a prime possibility to blunt Iran's spreading influence in the Middle East.

But he also made clear that he does "not want our military involved in Syria," ruling out participation in a no-fly zone over the country.

 "We do need to make sure that the arms do not get in the wrong hands," Romney said, adding that sending weapons to Syrian rebels must be coordinated with Israel.

 Israel has also divided the campaigns, with Romney holding Obama's difficulty with Middle East peacemaking as evidence that he has failed to support a prime U.S. ally in the region.

Obama took office with new ideas about how to more effectively broker an Israeli-Palestinian peace agreement. Those efforts foundered amid continuing Israeli settlement construction in the occupied territories and Palestinian resistance to joining direct peace talks until it was too late.

 But Obama has increased military aid to Israel, collaborated on missile-defense projects and endorsed Israeli Prime Minister Benjamin Netanyahu's position that Iran must not be allowed to develop a nuclear weapon.

 "I will stand with Israel if they are attacked," Obama said - and Romney, soon after, said he would, too.