Trump vows to unleash ethanol at gas pumps as he woos Corn Belt

President Donald Trump promised to allow higher-ethanol gasoline to be distributed using existing filling station pumps, a move designed to boost support among corn farmers and biofuel producers in Iowa and other Midwestern swing states.

Trump announced the decision Saturday on Twitter, after a conversation with Senator Joni Ernst, an Iowa Republican who's been pushing for the change as part of her own re-election battle.

"Subject only to State approval, our important Ethanol Industry will be allowed to use the 10% Pumps for the 15% BLEND," Trump tweeted.

The move builds on the Trump administration's decision in 2019 to authorize the sale of a 15% ethanol-gasoline blend known as E15 year-round. Prior to that change by the Environmental Protection Agency it had been blocked for sale in the summer in many areas where smog is a problem.

Although Trump said the change would only need state approval, it wasn't immediately clear if some rulemaking would be required from the EPA to buttress the shift.

Ethanol lobbyists have argued the change could encourage more filling stations to offer E15, expanding sales of corn-based ethanol. Most gasoline sold in the U.S. is a 10% blend known as E10.

"GREAT news for Iowa -- our biofuel community, farmers and economy," Ernst said on Twitter. "This is what I've been pushing for since we secured E15 year-round: increased access to higher blends of ethanol and more choice at the pump for consumers."

Ernst is in a tight race against Democrat Theresa Greenfield, a political newcomer. Polls show the race too close to call.