According to the Gallup daily tracking poll released on Tuesday, 51 percent of U.S. adults said they disapproved of how Obama was handling his job, compared with 42 percent who approve.
The poll reflects a one-point change from Monday, when Obama's disapproval number hit 50 percent for the first time.
Republicans were quick to point out the new number to further their argument that Obama is a liability to Democratic candidates in this fall's midterm elections.
Obama this week has been on a campaign push. He's appearing at a fundraiser for Sen. Patty Murray (D-Wash.) on Tuesday and has campaign events in Ohio and Florida later this week. Obama headlined a fundraiser Monday for the Democratic Congressional Campaign Committee in Los Angeles.
The movement in the poll doesn't amount to any sort of seismic shift in public opinion toward Obama; the Gallup daily tracking poll represents a rolling average of public opinion in the pollster's last three days of opinion surveys.
But the fact that Obama's numbers are steadily becoming more negative — combined with the fact that another Gallup poll showed Republicans with their widest advantage yet in generic congressional balloting — have Republicans feeling confident, for now, about their chances in November's mid-term elections.
The latest Gallup poll, conducted August 14-16, has a 3-percent margin of error.