Public Backs Military Option if Iran Balks on Nukes

That consensus includes 71 percent of Republicans, 51 percent of Democrats and 66 percent of independents. Twenty-four percent believe that the U.S. should avoid military conflict even if Iran does develop nuclear weapons.

A report in Sunday's New York Times said a confidential United Nations analysis concluded that Iran now had "sufficient information" to design and produce a workable nuclear bomb, although National Security Adviser James Jones said Sunday on CNN that U.S. officials still believed Iran was one to three years away from having nuclear capability.

Sixty-three percent support the idea of the U.S. having direct negotiations with Iran, with 28 percent opposed -- a change from Pew's survey in Sept. 2006, when the ratio for support was 54 percent to 32 percent. That view is shared across party lines.

That said, 64 percent do not believe negotiations will bear fruit, compared to 22 percent who are more optimistic in that regard.

Fifty-one percent of Americans say they have a great deal of confidence in President Obama to deal with Iran, 17 percent say a fair amount, 44 percent say they do not have too much confidence and 20 percent say they have none at all.