After the U.S. Environmental Protection Agency approved 31 waivers for oil refineries that ethanol producers say destroys demand for corn, support for the president among Iowa agriculture is being tested. 

Democratic presidential hopefuls — one of whom will be Trump’s eventual opponent — hope to appeal to Iowa’s agriculture and renewable fuels industry by criticizing the president on the issue. 

In Des Moines on Tuesday, Sen. Amy Klobuchar, D-Minn., said President Trump “gut punched” the renewable-fuels industry by allowing the EPA to approve the waivers. She spoke alongside former U.S. Agriculture Secretary Tom Vilsack and former National Corn Growers Association President Pam Johnson.  Throughout her campaign, Klobuchar has made her Midwestern roots a key part of her presidential pitch to Iowans, including at the Iowa State Fair.

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Others addressed the issue in a flurry of campaign emails and statements — including New Jersey Sen. Cory Booker, former Maryland Rep. John Delaney, and Hawaii Rep. Tulsi Gabbard — calling for the EPA to say the waivers hurt farmers.

“We’ve got a president who is actively undercutting Iowa farmers in favor of Big Oil,” South Bend, Indiana, Mayor Pete Buttigieg wrote in a tweet. Buttigieg also released a policy plan to address rural concerns ahead of his appearance at the Iowa State Fair in early August. 

We’ve got a president who is actively undercutting Iowa farmers in favor of Big Oil—and he’s doing it while his trade war with China decimates farmers’ bottom lines. When I’m president, I’ll end this administration’s abuse of small refinery exemptions. https://t.co/peDg0jjqKx

— Pete Buttigieg (@PeteButtigieg) August 28, 2019

Former Vice President Joe Biden said in a Aug. 21 forum in Ankeny that major oil companies should “meet the criteria that is set.”

Trump responded to outcry from Iowa and other Midwestern states in a tweet Thursday morning promising a “giant package” to help the ethanol industry.

Trump’s response, though without details, comes after several weeks of bipartisan pressure from Iowa politicians and corn advocates for Trump to rectify more than $1 billion gallons of biofuel demand lost, because the EPA retroactively waived biofuel blending requirements for 31 refineries for 2018. 

Iowa produces nearly one third of the nation’s 15 billion-gallon minimum ethanol blending requirements, according to the Iowa Renewable Fuels Association.

“The Farmers are going to be so happy when they see what we are doing for Ethanol, not even including the E-15, year around, which is already done. It will be a giant package, get ready! At the same time, I was able to save the small refineries from certain closing. Great for all!” Trump wrote on Twitter Thursday morning.

The E-15 Trump referenced is a higher-ethanol blend fuel that his administration allowed to be sold year-round, a change from previous years when it couldn’t be sold in the summer. 

The EPA sets requirements each year for the amount of biofuels that must be infused into the nation’s motor fuel supply. Some small oil refineries can apply for exemptions from that obligation if they can prove the requirements disproportionately hurt their business. 

During the Trump administration, 85 oil exemptions were approved from 2015-18, double what was waived during the Obama administration from 2011-14. Some of the waivers were given to refineries controlled by nationwide companies including Exxon.

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Stu Swanson, a north-central Iowa farmer and member of the Iowa Corn Growers Association, said he’s growing weary of the emotional toll of uncertainty with the Trump administration’s policies that affect agriculture. 

Although he doesn’t sell corn for ethanol, he said the reduced demand keeps the prices of corn for feed low as well. Prices for corn peaked at $7 in 2013 and have steadily dipped to between $3.50 and $4. 

Monte Shaw, the executive director of the Iowa Renewable Fuels Association, told The Daily Iowan the IRFA is asking the Trump administration to complete two solutions — redistribute the 1.4 billion gallons of ethanol waived and estimate how many waivers would be approved next year so the ethanol industry could prepare. 

One ethanol plant in Iowa suspended its business in late July.

Shaw said that he believed that unless the Trump administration fixed the situation, the waivers would have political consequences for Trump ahead of 2020.

“I’ve had a lot of conversations with rural voters in parts of the state that are pretty red,” Shaw said. “They say, ‘You know, I’m not sure I can vote for a Democrat, but I’m not going to vote for the guy who lied to me either.’ ”