Ethanol waivers are becoming a central issue in the battle for the farm vote — and the issue heated up this week with three straight days of President Donald Trump and former Vice President Joe Biden trying to outdo each other with their support of the program and with it, Midwestern farmers.

It is the latest of several maneuvers in the battle for the votes of farmers and rural residents, the majority of whom typically vote Republican, in Minnesota and other farm states.

Minnesota Farm Bureau officials recently got 40 minutes of time in a virtual conversation with Trump. Former Agriculture Secretary Tom Vilsack held a similar call with the group for Biden, the Democratic presidential candidate.

In many areas of the state, signs supporting Trump vastly outnumber Biden signs. But both candidates and their surrogates continue to press their case with a voting bloc that could be critical in the presidential election.

In Isanti County in east-central Minnesota, Ron Drude's phone rings frequently with political phone calls from supporters of both presidential candidates.

This week's volleys started Monday, when the Environmental Protection Agency refused 54 production waivers that would have reduced the number of gallons of ethanol required to be produced from homegrown corn.

In a statement, EPA Administrator Andrew Wheeler said the action demonstrated "President Trump's promise to promote domestic biofuel production, support our nation's farmers, and in turn strengthen our energy independence."

Biden countered Tuesday with an attack on Trump for the EPA's earlier approval of 85 ethanol production waivers — four times the historical average. The waivers reduced ethanol production by 4 billion gallons and reduced corn sales by 1.4 billion bushels, Democrats said.

At the core of the waivers is the Renewable Fuel Standard (RFS), which mandates the number of gallons of corn ethanol the country must produce each year and is critical to Minnesota's corn industry.

On Wednesday, Minnesota Farmers Union president Gary Wertish, Vilsack, Sen. Debbie Stabenow, D-Mich., and Rep. Angie Craig, D-Minn., joined several farmers to blast the EPA's dismissal of retroactive ethanol waivers as a cynical vote-getting strategy that was "too little, too late."

"You don't get patted on the back for doing what you're supposed to do," Craig said in a virtual news conference set up by Biden's campaign.

Trump created or contributed to many of America's agricultural problems of the past four years by cutting ethanol production and imposing tariffs, Wertish said.

"You have farmers with a Trump sign at the end of their driveway," said Wertish, a lifelong Minnesota farmer. "But they're mad at the EPA" for cutting 4 billion gallons of ethanol from production using waivers favored by the oil industry."

"Well, it's Trump's EPA," he said. "There seems to be a disconnect there."

Craig said she has been visiting farms in her district where corn and soybean growers were frustrated at the administration's approach to the RFS. In addition to waivers, the government has yet to set ethanol production quotas for 2021.

Democrats also blame farm troubles on a trade war the Trump administration started with China in an effort to stop that country from undermining U.S. businesses and stealing U.S. intellectual property.

U.S. tariffs on Chinese imports forced American businesses to pay the U.S. government and decide whether to pass the charge along to U.S. consumers. U.S. businesses paid roughly $38 billion in tariffs in 2016. By 2019, with the trade war, the number jumped to $78 billion, according to the Brookings Institution.

Meanwhile, Chinese retaliatory tariffs on U.S. soybeans crushed the soybean export market at a time when it was reeling from low commodity prices and bad weather.

The Trump administration gave out up to $24.5 billion in 2018 and 2019 in Department of Agriculture market facilitation payments to farmers. The government money directly subsidized farmers hurt by the trade war to help keep them solvent.

Wertish acknowledged that the money was badly needed by trade war casualties, but he said Trump's trade policies necessitated the aid. He called the payments "a bribe" to retain farmers' support.

Still, Minnesota Farm Bureau president Kevin Paap predicted ethanol would play a bigger role in the farm vote than retaliatory Chinese tariffs that hammered soybean sales.

"The big question is where this [next] president is going to be on the RFS," Paap said as he took a break from cleaning a combine on his corn and soybean farm in Blue Earth County. "I can see smoke stacks of two ethanol plants from my farm. One is open. The other is not."

Some minds are already made up.

In Isanti County, Drude, a longtime Democrat who retired from farming but still rents his land to other farmers, has seen "a surprising number of Trump signs" that seemed to "spring up overnight like mushrooms."

He has seen evidence that the Trump campaign is well-organized in rural areas. He will call soon to get Biden signs, which he will plant along extensive road frontage to balance out Trump signs.

One of those Trump supporters is Andrew Herdegen, 34, who was on his tractor in McCloud County earlier this week trying to finish gathering hay.

The president, he said, "is trying to produce a new world economy that gives American farmers a fair shake" while Democrats "import products into our country that we could produce."

Bob Worth and his son farm 2,300 acres of corn and soybeans in Lincoln County in southwest Minnesota. Worth has not been contacted by either presidential campaign, but he says Trump signs in his part of the state outnumber Biden signs at least 10 to one.

Worth doesn't think cuts in ethanol production are enough to cost Trump a majority in farm country.

"People are frustrated more with the Democrats," he said. "The Democrats have not done anything except impeach the president."

Jim Spencer • 202-662-7432