A clash over the reconciliation bill’s effect on the federal debt imperils efforts to pass the sweeping Republican tax and spending bill in the Senate.

The reconciliation legislation, the One Big Beautiful Bill Act, would extend much of the tax cuts from the 2017 Tax Cuts and Jobs Act, add new tax cuts, and increase spending on border security. Those additions to the federal deficit would be partially offset by spending reductions, including through the Medicaid and food stamp programs. Because the legislation would add trillions of dollars to the federal debt, it faces scrutiny in the Senate, particularly from fiscal hawks such as Sen. Ron Johnson of Wisconsin, who maintains that federal deficits are already too large.