US midterm elections 2026: Record diesel prices hit at worst time in key battleground states

Record-high diesel prices are coming at the worst possible time for Iowa farmer Kinser Jensen.

He’d held off buying diesel after the cost skyrocketed at the beginning of the Iran war, hoping prices would recede. But harvest is just weeks away, and with it the heavy fuel demands involved in bringing in the crop. Diesel is only getting more expensive.

“I’m not exactly sure what we’re going to do,” said Jensen, 32, who runs a 3,400-acre corn and soybean farm with his 62 year-old father in northeastern Iowa. “At some point here, I’m just going to have to pull the trigger and buy the fuel.”


Jensen, a 2024 Donald Trump supporter who gravitates toward Republicans, said the high diesel prices are causing him to question how farmer-friendly the Trump administration really has been.

The costs of diesel and home heating oil have surged faster than gasoline in recent months, particularly hammering states that are critical battlegrounds in November’s midterm congressional elections — just as mail-in ballots arrive.

In Alaska, many remote communities rely on diesel generators for electricity. The climate is harsh, freight moves over long distances and per-capita usage of diesel and home heating oil is more than four times the national average. In Midwest states like Iowa, Kansas and Nebraska, farm equipment runs on diesel. In Maine and New Hampshire, large numbers of homeowners depend on heating oil to get through cold winters.

Grain Belt farmers are engaged in an energy-intensive race against time and weather, involving heavy combines that crawl across fields cutting, pulling, threshing and cleaning crops; tractors to tow grain carts alongside; and trucks to deliver the harvest to silos and grain elevators. Many homeowners right now are filling heating oil tanks for the first time since spring.

In rural Windsor, Maine, 75-year-old retiree Steve Hoad said he is confronting a choice between putting off repairs to his farmhouse or dipping into his savings because heating oil is costing him an additional $230 a month, based on the increase in prices since the Iran war started.

“It is a significant burden that I have to think about how I will bear,” Hoad said. “There aren’t a lot of options.”

Average retail US diesel prices crossed $6 a gallon for the first time ever last week and kept climbing to $6.27 on Monday, according to the American Automobile Association. As of Monday, they had jumped almost 70% since the US launched the Iran war in February.

Diesel and heating oil prices are tied closely because the two are nearly indistinguishable and produced through almost identical refining processes.

The Iran war has especially hit those fuels because the world relies on Middle Eastern crude oil to feed refineries that produce diesel and gasoline. The Middle East is also a critical exporter of diesel itself, but flows of refined products through the Strait of Hormuz remain sharply curtailed. Taken together with a ban on diesel exports from Russia — the world's second-largest exporter in normal times — global diesel supplies have tightened sharply.

The average retail heating oil price in Maine was $5.39 a gallon as of Sept. 8, more than 40% higher than before the start of the Iran war in February, according to state data.

Maine consumes more heating oil per capita than any other US state because half of all households rely on it as their primary heat source, according to the Maine Department of Energy Resources. New Hampshire, which also has a competitive Senate race, isn’t far behind.

Fuel costs often figure prominently in voters’ perceptions of presidential performance, said Kevin Book, managing director at Clearview Energy Partners, an independent research firm based in Washington.

The financial burden from the current price spike is hardest on lower-income and fixed-income households “that have to pay up this extraordinary premium in cash to heat their homes for the winter,” he added.

“These are the marginal votes that can decide close elections in swing states,” Book said. “High prices might be a reason you stay home” if you’re a Republican, or be motivated to vote if you’re a Democrat.

Democrats are harnessing that discontent.

At a US Senate debate over the weekend on Alaska’s Kodiak Island, home to about 12,000 people and 450 locally owned vessels, Democratic candidate Mary Peltola cited the impact of diesel costs on the fishing industry, which drives nearly the entire local economy and is a key private-sector employer in the state. Diesel not only propels fishing boats but powers their hydraulics and refrigeration.

“Diesel is getting more and more expensive for our fishermen,” Peltola said. “We need someone in DC fighting to lower our costs, not to jack up our costs.”

Former Ohio Democratic Senator Sherrod Brown, who’s challenging Republican Senator Jon Husted in a competitive race, has aired an ad featuring a farmer criticizing Husted’s votes supporting the Iran war and tariffs, citing higher diesel and fertilizer costs.

“At a certain point, it’s not just politics anymore,” the farmer says in the ad. “When you start taking money out of my pocket, it becomes personal.”

The Trump administration blames the record diesel prices on Ukrainian attacks that decimated Russia’s diesel exports, as well as the reduction in US refining capacity under previous Democratic presidents.

Trump said in a social media post on Monday that both Ukraine and Russia have agreed not to attack any energy targets. Ukrainian officials later said they were caught unaware by the announcement and no deal had yet been reached.

But diesel prices would not be at record levels if not for the conflict in the Middle East, said Jason Miller, a supply chain professor at Michigan State University. And after predicting for months that the Iran war would end quickly, Trump has now conceded that the conflict won’t end until after the midterms, leaving oil and gasoline prices elevated through the election.

Margins for making diesel fuel from crude oil were at record highs of near $115 a barrel as of Tuesday, indicating a severe shortage. The US Energy Information Administration predicted the country's distillate fuel stockpiles — which include diesel and heating oil — would dip below the 100 million barrel mark by the end of September, for the first time since 2003. Meanwhile, stockpiles of the fuels are just above their lowest levels on record on the East Coast.