Over on Power Line there's a discussion of the relation between gasoline prices and presidential popularity. The accompanying graph rather suggests a correlation
although you can see where other events overtook the effect such as the beginning of the Reagan economic boom, the effect of Bush I's breaking his "no new taxes" pledge, and the Bush II reaction to 9/11. A somewhat more rigorous analysis here suggests that while a president may well be held responsible for rising gas prices, bringing them down is of limited value. Current predictions of gas in the upper $4 range for the summer and possibly into the $5's in high tax locations like California do not bode well for the current administration.
More interesting in my mind is the second graph on Power Line that shows demand for gasoline has fallen to about 60% of what it was as late as 2007. I realize that a lot of people have purchased Prius's since '07, but they would have to represent about half the traffic on the roads to have that big an effect. I can think of several factors that could contribute to a 40% drop in gasoline consumption, but nothing that accounts for the bulk of it.