Diesel hit a record price in the U.S. on Friday, soaring to an average of $5.85 a gallon for the first time as the six-month war with Iran disrupts the world's flow of fuel. Because diesel is used for many freight and delivery networks, higher diesel prices mean higher transportation costs for a long list of everyday goods. This could add to Republicans' political challenges ahead of November's midterm elections, with voters already sour on President Donald Trump's management of the economy. AP-NORC polling this summer showed 2 out of 3 U.S. adults disapproved of how Trump is handling the economy.