As the 2020 Democrats begin campaigning heavily in Iowa, they're playing with a form of political dynamite known as the Green New Deal. Candidates who fully embrace could see it blow up in their hands, because it is red meat for the Democratic base, one key constituency in the first caucus state is deeply skeptical: corn farmers and ethanol producers.

"The Green New Deal would be devastating to rural America. The negative impact of what the Green Deal says would have a negative impact on the entire agricultural supply chain, from farmers to cattle owners, to drivers to ethanol refineries," Quad County Corn Processors CEO Delayne Johnson.

The Green New Deal, as written, would "replace every combustion engine vehicle," with something carbon neutral as part of "overhauling transportation systems in the United States to eliminate pollution and greenhouse gas emissions from the transportation sector." That is, no more biofuels.

"Out here in Iowa, we have retired widowed farmers who depend on the farms of their deceased spouses," Johnson said, expressing concern about the economic impact if Iowa is suddenly faced with a 40-45 percent surplus of corn.

Vermont Sen. Bernie Sanders, who is currently vying for first place in polls against former Vice President Joe Biden, has given the plan a full-throated endorsement.

"You cannot go too far on climate change. The future of the planet is at stake," Sanders said in March.

Massachusetts. Sen. Elizabeth Warren cosponsored the bill and tweeted out support for it, claiming that Americans "have no time to waste to address [climate change] head on." New York Sen. Kirsten Gillibrand said the plan was a necessary "moonshot" and "a measure of our innovation and effectiveness."

Al Giese, a former agricultural corporate executive who now works in biofuels, and also as a farmer, shared similar concerns. He also told the Washington Examiner that he wasn't sure what he was supposed to with all his corn if a Democratic administration suddenly made beef products illegal, a reference to an FAQ on the Green New Deal that mentioned getting rid of "farting cows."

"Farmers are very concerned over potential environmental regulations," harming their livelihood, Giese said. "The 2020 Democrats don't seem to show any interest in liquid fuel."

Iowa produced 4.35 billion gallons of ethanol and 365 million gallons of biodiesel in 2018, with renewable fuels accounting for 3.5% of Iowa's entire GDP. Over 48,000 Iowans work in the industry, and nearly 30 percent of all American ethanol is made from bushels of corn from Iowa.

Some in the 2020 field have been careful not to irrevocably embrace the Green New Deal and could benefit from appreciative farmers on caucus night.

“I see it as aspirational. I see it as a jump-start,” Minnesota Sen. Amy Klobuchar said on Fox News. “So I would vote ‘yes,’ but I would also — if it got down to the nitty-gritty of an actual legislation as opposed to, ‘oh, here are some goals we have,’ that would be different for me,” she added, saying she was "not for reducing air travel."

Former Colorado Gov. John Hickenlooper said in February that supporting the Green New Deal shouldn't be "a litmus test of what it takes to be a good Democrat."

Hawaii Rep. Tulsi Gabbard signaled support for the plan and taking "serious action to address climate change," but said she had "some concerns with the Green New Deal, and about some of the vagueness of the language in there."

South Bend, Ind., Mayor Peter Buttigieg echoed some of these concerns by terming the bill "more of a plan than it is a fully articulated set of policies" but still called it "exactly the right direction to be going in."

Biden, meanwhile, has been silent on the issue altogether.

Asked recently about the Green New Deal, New Jersey Sen. Cory Booker didn't quite say he backed it. "Doing nothing is not an option right now because our planet really is in peril," told a group of Iowans on a campaign stop. "I believe that America should lead, and it should lead boldly."

The Green New Deal was introduced by freshman Democratic Rep. Alexandria Ocasio-Cortez of New York in February. Many policy analysts and economists dismissed the program as farcical, pointing out how the cost, at $93 trillion, alone would be greater than the entire economy of the United States.

Every farmer and ethanol producer who spoke with the Washington Examiner was comfortable with stronger government regulations to lower the country's carbon emissions, and none disagreed with the scientific consensus that humans play a role in the changing climate. But they say biofuels lower carbon emissions are part of the solution.