TELTOW, GERMANY - SEPTEMBER 13: Stalks of corn stand under a blue sky during harvest on September 13, 2012 near Teltow, Germany. The annual corn harvest is underway in the German state of Brandenburg, where corn is widely planted and used for animal feed as well as the produciton of biofuels. Analysts recently predicted that German corn farmers are likely to benefit from global warming, as higher temperatures will mean an earlier planting season.National Journal

Biofuels backers and a coalition of organizations opposed to the renewable-fuel standard will line up on Thursday to give testimony during the Environmental Protection Agency's public hearing on the proposed 2014 mandate. At the same time, interest groups are also making a push to shift the conversation onto the RFS outside the Beltway.

Americans United for Change, a progressive advocacy group, is launching an ad buy suggesting that cuts to the renewable-fuel standard will hurt American farmers and the domestic economy.

The ad, which will air primarily in the Des Moines, Iowa, market — in the heart of corn country — urges viewers to ask EPA to leave the mandate intact and directs them to visit the website www.savetherfs.com.

"Tell the EPA to stand with Iowa farmers and small towns, not big oil," the narrator says, while images of a farmer standing in a corn field and idyllic street scenes appear in the background. "Tell the EPA: Don't gut the renewable-fuel standard."

In a statement, Brad Woodhouse, the president of AUFC, continued the attack on big oil: "The industry that brought us the Gulf oil spill loves the new RFS rule as it stands and would love nothing more than to keep rural America quiet until the ink is dry. That's why it's incredibly important that Americans in the heartland make their voices heard, because the strength in numbers of those who benefit from the RFS can beat big oil's deep pockets."

Watch the full ad here

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