And 56 percent said they opposed Washington's financial intervention to save the troubled automaker, while 35 percent supported it, and 69 percent say they are concerned "a great deal" or "quite a bit" about that effort.
About 48 percent back Obama's ban on harsh interrogation practices widely seen as torture, including waterboarding, while 41 percent oppose it.
Obama's job approval rating has slid to 56 percent from 61 percent in April, according to the survey, which had an error margin of plus or minus 3.1 percentage points.
Among independent voters, Obama fell from 60 percent approval versus 31 percent to 46 approving against 44 disapproving.
The poll found that just 37 percent of Americans think Obama has taken on too many issues, while 60 percent say he is fighting on many fronts because the country faces many pressing problems.
While a majority of respondents worried about the size of the soaring US federal budget deficit, just six percent blamed Obama for the gap, while 46 percent blamed former US president George W. Bush, 21 percent said the Democrats in Congress, and seven percent said the Republicans in Congress.
Moreover, 72 percent said that the sour US economy was something Obama inherited, and 46 percent said they expected things to improve in the coming yuear -- up eight points from April.
Obama also got good news about his Supreme Court nominee, Judge Sonia Sotomayor, with half of respondents saying she is qualified for the job, versus 13 percent who said she is not.
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