But unlike some of those issues, Romney's campaign hasn't put serious money behind the foreign policy line of criticism.
Paid TV ads in key states don't largely mention international affairs. The third-party group American Crossroads has a produced a Web video assailing Obama's foreign policy, but it's not on the air. Polls show foreign policy far down on the list of voters' concerns and Obama leads Romney on the issue.
Romney's campaign had spent much of the year focusing its argument against Obama's handling of the economy.
Then came Sept. 11, and as unrest flared in the Middle East, Romney issued a late-night statement assailing Obama before it was clear that Stevens and three other Americans had been killed in the terrorist attack on the consulate in Benghazi. The timing of Romney's initial response prompted heartburn within the GOP. Yet, Romney pressed ahead with his criticism that Obama was a weak leader whose posture abroad was hurting U.S. interests, and congressional Republicans have piled on about the administration's changing statements on the Libya attack.
Romney campaign aides said internal polls showed the criticism of Obama's foreign policy resonating with voters in the days after Stevens' death. But any traction Romney was getting on that front was stunted when a video surfaced of Romney telling donors that 47 percent of Americans believe they are victims entitled to government assistance. Obama has highlighted that comment repeatedly in TV ads and at campaign rallies, building on his post-convention momentum.
Since then, the administration's statements on Libya have evolved, with officials struggling to explain just what happened in Benghazi.
White House adviser David Plouffe seemed to struggle Sunday on NBC's "Meet the Press" when pressed on the matter.
"This was an event obviously, a complex event. We're only talking about a matter of weeks here," Plouffe said. "So as information was arrived at, as determinations were made, that was shared with the American people. And I think again the focus needs to be how do we make sure that our facilities and our ambassadors and our personnel are secure going forward."
Republicans have looked to capitalize, raising questions about why the consulate in Benghazi wasn't better protected and why the ambassador wasn't traveling with more security.
"It was either willful ignorance or abysmal intelligence to think that people come to spontaneous demonstrations with heavy weapons, mortars, and the attack goes on for hours," Sen. John McCain, R-Ariz., told CNN on Sunday.
AP White House Correspondent Ben Feller, AP News Survey Specialist Dennis Junius and Associated Press writers Steve Peoples and Matthew Daly in Washington and Julie Pace in Henderson, Nev., contributed to this report.
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