President Donald Trump made an off-hand remark this week that undercuts what a political organizer has found to be the message that resonates most with rural voters.

Republican senators were blindsided this week when the president casually mentioned the U.S. would start importing beef from Argentina to offset soaring meat prices, and Democratic organizer Matt Hildreth told The New Republic that farmers could see that move as a betrayal of their long-standing support for him.

"There’s not actually a ton of farmers in rural America anymore, the industry has been largely consolidated," said Hildreth, whose family has been farming for generations and who runs ruralorganizing.org. "But when the farmers are pissed off, people hear about it and they pay attention. And right now, people — whether they’re actively involved in agriculture or just their grandparents were actively involved in agriculture, and maybe now they work in healthcare — they look at what’s happening and they see it for what it is."

The president has a choice to make between screwing over his billionaire allies in Argentina or screwing over farmers, according to Hildreth, and his decision could expose his most enduring message as a lie.

"When we look back at the polling over the last couple of years, the most popular message in rural America was that we need to end the corruption in Washington, D.C.," Hildreth said, "and Donald Trump’s message about 'draining the swamp' has been the most popular message that we’ve seen in rural America across the board, and I think that people are starting to see this corruption and the fact that the only people who seem to be benefiting right now are Donald Trump’s billionaire friends, and I think that’s something that’s cracking through."

"I don’t know if it’s going to be a dam break, but I think the margins are starting to shift in places that I actually would not have expected," he added, "and I think that’s a really good thing."

Farmers are the most trusted voices in rural America, he said, so hurting them could do major political damage.

"Now you have Donald Trump, who’s just kind of off the cuff — or seemingly off the cuff — talking about importing beef from Argentina, and that would put American farmers in direct competition with the beef coming up from South America, and that’s going to bring down the price of beef," Hildreth said.

Farmers who raise cattle don't actually make much money most years, he said, but this year was shaping up to be bountiful.

"Most years, people who do cattle lose money, or they just barely break even," Hildreth said. "But every once in a while, you have a year that’s going to pay all of your bills, pay all of your debts, and that was going to be this year."

"This is the first really good, positive thing in the market for farmers," he added. "Now, for consumers, it’s a problem — but for farmers, they were going to be making back their money this year. So when Trump is throwing this uncertainty out of nowhere into the markets, it’s absolutely hitting farmers when they’re already down — they’re already kind of uncertain about where things are going, and it’s really pulling out the rug from under them on that last lifeline they had, which was the beef prices that were supporting them."