President Barack Obama's job approval rating has dipped to its lowest level in nearly two years, a new NBC News/Wall Street Journal poll released Wednesday shows.
The president's overall job-approval rating stands at 45 percent, one point from his all-time presidential low — 44 percent — in August 2011.
In June, Obama's approval rating was 48 percent, according to the same NBC/WSJ poll.
The drop is explained in part, according to NBC, by an erosion in support for Obama among African-American respondents: 78 percent approve of his job, down from 88 percent in June and 93 percent in April.
George Zimmerman's acquittal in the shooting death of Trayvon Martin could explain the slide, the pollsters say.
The poll was conducted in the days following the verdict and includes responses that were received before and after the president's recent comments addressing Martin's death.
The slide in the president's approval rating comes as he is set to embark on an ambitious series of six speeches laying out a sweeping vision for America’s future. The first, scheduled for Wednesday, will focus on the economy.
The poll also found a staggering 83 percent of Americans disapprove of Congress — an all-time high for the survey. And nearly 60 percent of American adults said they would replace "every single member of Congress if they had such an option."
"There is a palpable unhappiness with Washington," Peter D. Hart, a Democratic pollster who helped conduct the survey, said in a release. "Outside the Beltway, voters are saying, 'You don't get it.'"