Economic struggles are becoming a significant political issue for Republicans in states long considered party strongholds

Farmers have spent months feeling the squeeze as costs for inputs like diesel, fertilizer and seed have soared due to refinery constraints and supply disruptions tied to the Iran war.

Diesel averaged $6.30 per gallon nationwide on Friday, more than 70% higher than a year ago, according to motor club AAA. The surge has been especially painful during harvest season, when farmers depend heavily on fuel to operate machinery and transport crops.

The U.S. Department of Agriculture projects that net farm income will decline by 2.6% this year as production expenses rise by 4.5%. Fuel and oil expenses alone are expected to jump nearly 30%, according to the agency’s September forecast.