There's one more reason why a higher ethanol-blend requirement is a hot-button issue: drought.

Farmers and farming advocates are asking the Environmental Protection Agency to ease up on ethanol requirements for the U.S. fuel mix because drought conditions through much of the country are causing corn prices to spike, NBC News reports.

Livestock producers and cattlemen who use corn for feed say that ethanol requirements are exacerbating the recent jump in corn prices, have surged as much as 60 percent in recent weeks due to the drought. With that in mind, the EPA is in discussions with the USDA and is watching crop estimates, but has not yet taken any action on the biofuel requirement.

Even before the skies decided to stop dropping enough water, the idea of boosting ethanol-mix requirements has been a controversial one. Opponents say higher ethanol mixes haven't been adequately tested and may damage engines. Proponents say more ethanol use may cut pollution and will reduce dependency on foreign oil. The EPA officially approved the public sale of E15 – gasoline mixed with 15 percent ethanol – in June.