Professor Pollkatz has a very enlightening
graph demonstating the relationship between Bush's approval rating (an average of recent polls) and the price of gasoline. Basically, when the price of gasoline goes up, Bush's approval falls, and what is important right now, when the price of gasoline goes down, Bush's approval goes up.
The price of gasoline at the pump has gone down 15 cents in the past couple of weeks; it is now at $2.87 (these are national averages, YMMV). Gasoline futures are also dropping significantly, so the pump price will continue to decline. In addition, gasoline prices have a cyclic decline in the Fall.
Right now Pollkatz's poll of polls has Bush's approval rating at 37.3. I think that based on gasoline prices we can expect Bush's approval rating to hit 40 within a couple of weeks and stay above that level. This is bad news for our chances November. If this election is seen as a referendum on Bush, then if Bush's approval keeps on going up, we will be fighting an uphill battle to take back either house in November.