The battle over Colorado’s proposed $46.8 billion spending plan for next year shifted to the state Senate, which must decide whether to acquiesce to changes made by the House.

The senators could also decide to adopt their own changes, which would force the two bodies to reconcile their differences.

The state constitution requires a balanced budget, although that rarely stays balanced for long, and this year, lawmakers must plug a deficit of more than $1 billion. The proposed budget is actually bigger than the current year’s spending plan, driven by Medicaid costs.

In the Senate, the budget is sponsored by Joint Budget Committee members Sens. Jeff Bridges, D‑Greenwood Village, Barbara Kirkmeyer, R‑Brighton, and Judy Amabile, D‑Boulder.

Senators will consider several House‑passed amendments, including one that removes Colorado Parks and Wildlife’s ability to use about $260,000 in general fund dollars to acquire additional wolves for the state’s reintroduction program. Another House amendment restores nearly $240,000 in cash funds and three full‑time employees to the Treasurer’s Office for the Unclaimed Property Trust Fund.

There is little room for major changes, as the Joint Budget Committee worked to close a $1 billion-plus budget hole in drafting the plan.

Democrats have attributed the shortfall to the federal budget passed pushed by the Trump administration, while Republicans argue that state Democrats created the state’s fiscal woes by overspending, expanding government and refusing to make the necessary cuts while knowing a huge deficit was looming.

Driving the fiscal crisis is spending in the state Medicaid program, which provides health coverage to low-income women and children. The program is beset by allegations of fraud and abuse, in addition to expansion programs approved by legislators that are costing the state significantly more than the original estimates.

A program that provides health coverage to pregnant women and children illegally staying in the U.S., for example, is costing the state four times more than estimated.

Cover All Coloradans, initially estimated in 2022 by nonpartisan fiscal analysts to cost about $27 million in general funds in the 2025-26 budget, instead cost nearly $90 million in general funds in 2025-26 and could cost more than $112 million in the 2026-27 budget.

Legislators are considering a proposal to cap children’s enrollment in the program.

The state budget stalled in the House, where Republican Rep. Brandi Bradley asked that the 661‑page bill be read at length.

Lawmakers ultimately passed the budget on Saturday, with all Republicans except Rep. Rick Taggart of Grand Junction voting against it. One Democrat, Rep. Bob Marshall of Highlands Ranch, also opposed the bill.

The budget consists of a budget bill and 64 accompanying measures, known as orbitals, all of which were approved by the House, most with bipartisan support.ˆ

Once the budget clears both chambers, it will head to the governor, who may veto specific provisions but cannot add new ones.

Reporter Marianne Goodland contributed to this article.