At times recently, Barack Obama almost seems to be trying to help make John McCain's case that he should be president because of his superior national security experience and knowledge. Obama has done so by displaying his own inexperience with imprecise statements on issues from Iran to Israel.

But McCain has been less than flawless in playing his supposed strong suit. And he faces a more basic problem: positions out of sync with the views of the public.

Indeed, as some recent polls have shown, this presidential election could hinge on whether voters are swayed more by the candidates' experience or their positions.

The public recognizes McCain's experience. A recent ABC News-Washington Post poll gave him a one-sided advantage on the question of who has better experience to be president and the better knowledge of world affairs.

That's hardly surprising, given McCain's Navy background, his service, his more than five years as a prisoner in Vietnam and a congressional career that includes years on the Senate Armed Services Committee. More recently, he was one of those most responsible for the renewed military drive in Iraq known as the "surge."

And his advantage has not diminished much from a series of verbal errors: understating U.S. troop strength in Iraq; mistakenly saying al-Qaida extremists trained in Iran were sent to Iraq; and Wednesday's comment on NBC's "Today" show that it's "not too important" to estimate when U.S. troops will come home.

Indeed, despite public skepticism over the Iraq policy McCain has supported, some surveys show that Americans believe he would do a better job handling the issue, although his edge has been slipping.

Obama, meanwhile, has done little to show mastery of national security details and nuance to rival McCain's. This could damage him if further examples emerge during high-profile debates or other joint appearances yet to come.

Last week, the Illinois senator had to backtrack from telling the pro-Israel lobby AIPAC's annual policy conference that "Jerusalem will remain the capital of Israel, and it must remain undivided."

Israeli-Palestinian peace talks, he conceded a day later, will determine its status.

Obama also appeared to retreat somewhat from his willingness to meet leaders of such U.S. foes as Iran, Venezuela and Cuba without preconditions in his first year in office.

"I have no intention of sitting down with our adversaries just for the sake of talking," he told AIPAC. "But as president of the United States, I would be willing to lead tough and principled diplomacy with the appropriate Iranian leaders at a time and place of my choosing — if, and only if, it can advance the interests of the United States."

Aside from his oft-stated goal of withdrawing U.S. combat forces from Iraq within 16 months, no Obama position has come under sharper fire from McCain than his talk of meeting Iran's Mahmoud Ahmadinejad.

But the public seems to think it's a pretty good idea.

A Gallup poll released last week showed that nearly three in five respondents thought it would be good for the U.S. president to meet the Iranian president. A slightly higher proportion thought the next president should meet other top U.S. foes, too.

A similar dichotomy is evident on Iraq.

Though the public feels McCain might do a better job of handling the situation, three in five Americans say the U.S. intervention is a loser that the next president should end.

That proportion hasn't changed much, despite some military progress from the surge. Typical is the most recent CBS News poll showing that 62 percent thought the effort was going very or somewhat badly, and about the same percentage opposed keeping large numbers of U.S. troops there two additional years.

McCain has little choice but to count on the fact most Americans will believe his experience will better qualify him to handle Iraq. Obama has to hope voters will follow their instincts and favor the man who will bring the troops home sooner.

Whichever one is right is likely to be the next president.

Carl P. Leubsdorf is Washington bureau chief of the Dallas Morning News. Reach him at cleubsdorf@dallasnews.com.