Americans by a broad 19-point margin support the nuclear deal with Iran announced last week, even as two-thirds in an ABC News/Washington Post poll express skepticism it'll work -- and relatively few give Barack Obama credit for bringing it to pass.

The public by 56-37 percent backs the agreement, a signature foreign policy goal of the Obama administration. It lifts economic sanctions against Iran in exchange for Iran agreeing not to produce nuclear weapons and allowing international inspectors to monitor its nuclear facilities.