This is controversial.
The left would be correct by arguing that Obama actually broke his promise and failed miserably to continue the eco-friendly trend in energy price increases he inherited from the previous green administration. Then again, the regime can always blame the falling prices for energy, gasoline --and coal as well-- on the obstructionist Republican controlled House that ended the glorious energy inflation we had with the Pelosi-led 111th Congress. They just won't mention the abysmal energy deflation with the 110th...
The economics of this is simple enough, energy prices are volatile and for a few years now they've sloughed off. The politics is easy to grasp too although it pretty much means we throw logic out the window.