President Trump’s continued trade war with China has Republican legislators representing the nation’s rural farming communities breaking ranks, given how hard China’s retaliatory tariffs on agricultural goods are hitting America’s heartland.

The president more than doubled tariffs, from 10% to 25%, on Chinese imports last week and has vowed to levy tariffs on another $300 billion in Chinese goods. In response, China has levied its own tariffs for the second time this year, primarily taking aim at the nation’s agricultural sector. China is the world’s second-largest importer of soybeans and wheat.

Iowa Sen. Chuck Grassley, R-Iowa, the Senate Finance Committee Chair, commented on Trump to the Washington Post that would often make headlines around the country in other administrations.

“I’m not sure if you talk to him face to face, he hears everything you say,” said Grassley.

Often a staunch ally, Grassley has been increasingly critical of the president’s trade policy, given his state’s reliance on corn exports.

Other hardline Republicans also are taking exception with the trade war, which the president initially characterized as temporary. However, the New York Times reported on Wednesday that tariffs may be here to stay.

Missouri Sen. Roy Blount, a top Republican leader representing a major soybean producing state, said Tuesday, “They can feel it. The farm community up ‘til now has really supported the president without flinching. But eventually you flinch.”

Although, Blount also added, “if you’re going to have a trade fight, the trade fight to have would be the China fight.”

Roughly 75% of voters who carried Trump into the White House reside in states heavily dependent on agricultural exports, and a drawn-out trade war could significantly impact his base going into the 2020 presidential election.

Sen. Pat Roberts, R-Kan, when asked the level of patience among farmers in his state regarding the escalating trade war, held up a thumb and index finger on one hand, with a small space between, indicating a narrowing of support.

“Ultimately, nobody wins a trade war unless there is an agreement at the end,” said Senate Majority Leader Mitch McConnell, R-Ky.

Meanwhile, the president has shown little concern regarding his party's apprehensions about prolonged trade squabbles.

“I love the position we’re in,” he said, earlier this week. “It’s working really well.”