The poll released Thursday by Quinnipiac University in Connecticut says Obama's approval rating in Ohio has slipped to 36 percent. The same survey in May gave him a 39-percent approval rating.
The poll found a strong partisan divide when it comes to Obama, with an approval rating of just 4 percent among Republicans and 74 percent among Democrats.
Thursday's poll also says 49 percent of voters approved of the job Democratic U.S. Sen. Sherrod Brown is doing, while 40 percent approved of the job done by U.S. Sen. Rob Portman.
The survey of 1,366 Ohio voters was conducted by phone from July 24-28. It has a margin of error of just under 3 percentage points.