A deeply polarizing farm bill narrowly passed the House on Thursday, a month after the legislation went down to stunning defeat after getting ensnared in the toxic politics of immigration.

The legislation, which passed 213 to 211 with 20 Republicans joining Democrats in their unanimous opposition, includes new work rules for most adult food-stamp recipients — provisions that are dead on arrival in the Senate. The massive legislative package overseeing more than $430 billion of food and agriculture programs over five years contains a host of measures aimed at strengthening farm subsidies, expanding foreign trade and bolstering rural development.

The bill was championed by a dwindling number of farm-district Republicans who feel duty-bound to deliver farm supports to their rural constituents. On the first go-round last month, this group lost out to an increasingly powerful cohort of conservatives who are more interested in winning political points on changes to welfare and immigration.

The tense divide between the two camps has huge implications for the future of food and farm policy in the United States, as well as the Republican Party itself. Even as the bill advances from the House, political analysts said, the tensions revealed in its lurching, divisive journey are likely to persist.

“People think, ‘Who cares about the Farm Bill? It’s so boring,’ ” said Adam Sheingate, a professor of political science at Johns Hopkins University. “But it’s a window into contemporary politics right now, particularly among Republicans — the struggles they face balancing the responsibility of governing against their ideological commitments.”

The most divisive element of the legislation passed Thursday are new, stricter work rules for most able-bodied adults in the food stamp program, the federal safety net that provides an average of $125 per month in grocery money to 42.3 million Americans. Under the proposal, adults will have to spend 20 hours per week either working or participating in a state-run training program to receive benefits.

Democrats and anti-hunger advocates say most states do not have the capacity to scale up case management or training programs to this extent. As a result, they argue, hundreds of thousands of low-income adults could end up losing benefits.

But Republicans have defended the plan as a bold way to make low-income adults more self-sufficient, and President Donald Trump tweeted on Thursday that he was "so happy" to see work requirements pass.

"The American Idea is so distinct: The condition of your birth should not determine the outcome of your life," said House Speaker Paul Ryan (R-Wis.) in a statement. "With the passage of this bill, we’re moving toward a poverty-fighting system where this kind of upper mobility is attainable for more Americans. This is a big deal."

The legislation also directs the Agriculture Department to reevaluate school lunch nutrition standards adopted under the Obama administration. It proposes to expand who counts as a “farmer” for purposes of subsidies, the compensation USDA distributes when crop prices fall below predetermined references.

It eliminates much of the Conservation Stewardship Program — aimed at encouraging farmers to address soil, air and water quality on their land — and folds it into the Environmental Quality Incentives Program, which is oriented toward compensating farmers for one-off conservation projects. And despite efforts by some lawmakers to end them, it extends federal supports for the U.S. sugar industry through programs that control the amount of foreign and domestic sugar on the U.S. market and guarantee a minimum price for producers if sugar prices drop.

“It is another shameful day in the House," said Rep. Earl Blumenauer (D-Ore.), who has championed liberal food policies, in a statement. "With passage of this bill, Republicans have turned their backs on family farmers and ranchers, vulnerable communities, the health of all Americans, and the environment."

Congress has not historically struggled to pass farm bills — though it has become increasingly difficult over the past 10 years. The farm bill comes up for reauthorization every five years and is generally passed on a bipartisan basis.

That bipartisanship is by design: In theory, the farm bill has something for everyone. It authorizes agricultural programs (such as crop subsidies and conservation incentives, popular in rural Republican districts), and programs that appeal to urban voters (think food stamps and farmers market promotion, both backed by Democrats).

Unlike the more partisan House, the Senate — where Democratic votes will be needed — has taken a bipartisan approach this year. The Agriculture Committee passed a version of the legislation embraced by both parties, and without the controversial food stamp changes in the House version, it's expected on the Senate floor next week. The two competing versions would ultimately have to be merged.

But in the House, while Democrats still vote en bloc to preserve the food stamp program — as they did this year — the Republican vote is splintering. That became evident during debate on the 2012 farm bill, which also initially failed on the House floor, and glaring during May’s farm bill vote. Conservative lawmakers defected to force a separate vote on immigration, embarrassing party leadership.

Earlier Thursday, conservatives got the immigration vote they wanted, but the legislation they championed failed, and a vote on a leadership-backed bill was postponed until Friday as the GOP churns in search of solution and the family separation controversy on the Southern border continues to unfold.

The reasons behind the farm bill fracture in the House are twofold, said Christopher Bosso, a professor of public policy at Northeastern University. First, the number of farm districts in America has shrunk as the rural population has fallen; and second, a wave of Republicans have come to power who value small government, spending cuts and immigration overhauls over the demands of their party’s dwindling farm-state constituents.

“I think the story of the farm bill is the story of the Republican Party,” Bosso said. “It is now split between traditional, rural conservatives — the kind who hold their noses and vote for the farm bill because they want those commodity programs — and the ideologues in the Freedom Caucus who think all spending is bad.”

Political observers say that is likely to make it difficult to pass food and farming legislation over the long term, even if Republicans were able to cobble together a coalition this time around. As the rural vote grows less powerful, farm-district Republicans increasingly need allies in the cities and suburbs.

Without them, the future of programs such as crop subsidies — which have already come under attack by both Democrats and conservative Republicans — looks increasingly uncertain.

“The house is still standing, but termites are eating at the floorboards,” Sheingate said. “Maybe it stands for a few more decades, but eventually the wind blows and it completely falls down. There’s just this constant, gradual erosion of the farm bill’s political basis.”

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