If he's responsible for lower oil prices he would also have to be responsible for the sacking of hundreds or even thousands of US jobs as new oil projects are mothballed because they aren't viable anymore.
Or more likely Saudi Arabia are driving the price down to punish Russia for backing Assad, stop US shale projects starting, and being pissed at Iran having sanctions lifted.
I've read that they might have to do something drastic like introduce income tax! Shock/horror.