Tomorrow could be the day.

One key landmark of President Obama's decline was reached some time ago:  He fell below 50% in the Gallup tracking poll.  It appears that tomorrow could be the next landmark.  Tomorrow, or sometime within the next week, it seems likely the Gallup tracking poll with indicate that more Americans disapprove than approve of Obama's approval as president.  (This happened in the Rasmussen tracking poll on July 24, but Gallup remains the gold standard for political journalists.)