The Senate has begun laying the groundwork for a half-trillion-dollar farm and food bill that would end unconditional subsidies to farmers, but House Republicans’ resolve to cut its biggest component _ food stamps _ by $13 billion a year dims its prospects of passing Congress.

The current five-year farm bill expires at the end of September, and the Senate Agriculture Committee on Friday released a draft of its plan to redesign safety nets that help farmers weather bad times while achieving some $23 billion in deficit reduction. The full committee is to vote next week on the plan, which consolidates conservation programs and takes several steps, such as stopping lottery winners from getting assistance, to make the food stamp program more accountable. Of that $23 billion in savings projected over next 10 years, $4 billion comes from food stamps.