The Senate Appropriations Committee voted 19-9 Monday morning to advance the Trump administration’s $67.4 billion Iran war supplemental, sending the package to the floor for a likely vote later this week even as the running U.S. service-member death toll since the war’s onset climbed past 350 and reignited demands across both parties for a long-deferred reckoning over war authority.

The committee’s markup, held in the Dirksen Building under unusually tight security, attached a series of conditions to the supplemental that administration officials had spent the weekend lobbying against. Among them: a requirement that the Pentagon submit to Congress a 90-day operational plan with stated objectives for any continuation of strikes inside Iranian territory, a prohibition on the use of supplemental funds to support combat operations beyond Sept. 30 absent congressional reauthorization, and a doubling of the war-related casualty assistance line from $6.3 billion to $12.1 billion to fund medical care, family travel and bereavement support for an expanding population of wounded troops and their families.

Senate Appropriations Chair Susan Collins, R-Maine, said the conditions were nonnegotiable. “We are not writing a blank check for an undefined war,” Collins said in remarks released after the vote. “We are funding a fight that is already underway, and we are demanding the accountability that Congress should have asked for six weeks ago.”

The vote came hours after the Pentagon updated its public casualty figures for the first time since Friday, confirming that an additional eight U.S. service members had been killed over the weekend in attacks attributed to Iran-aligned militias and Houthi forces. Four were killed Saturday in a rocket strike on a forward operating base near Erbil; two died Sunday from wounds sustained in earlier engagements; and two more were lost when a logistics convoy struck an improvised explosive device along a supply route in western Iraq. Pentagon spokeswoman Sabrina Singh told reporters Monday that the cumulative death toll among U.S. forces since the start of hostilities had reached 351, with more than 1,200 wounded.

“Behind every number is a family that did not sleep last night,” Singh said. “The department’s responsibility to those families is total.”

The crossing of the 350 threshold has shifted the political tone on Capitol Hill in ways aides in both caucuses described as palpable. Lawmakers who had been reluctant to publicly criticize the administration’s prosecution of the war began to speak more openly through the weekend, several said, particularly after a closed-door briefing Friday in which combatant commanders described an operational tempo that defense officials privately acknowledged could not be sustained at current force levels through the summer without additional rotations.

“What I heard on Friday changed my view of what the next 90 days look like,” said Sen. Mark Warner, D-Va., who chairs the Intelligence Committee. “We need a vote. The country needs a vote. I do not see how we avoid it any longer.”

The Kaine-Lee-Murphy War Powers resolution, introduced Thursday and now carrying 31 cosponsors across both parties, is expected to be discharged from committee and brought to the Senate floor by the end of the week under expedited procedures available to such resolutions. Senate Majority Leader Chuck Schumer, D-N.Y., who has not yet committed to a floor schedule, told reporters Monday that he was “in active conversation” with the resolution’s sponsors and with the administration. “I will not stand in the way of a vote that the constitutional process requires,” Schumer said.

Republican leadership remained publicly opposed to the resolution but visibly less unified than it had been a week ago. Senate Minority Leader John Thune, R-S.D., said the measure would “send the wrong signal at the worst possible moment,” but declined when pressed to say whether he would whip his caucus against it. Three additional Republican senators have privately signaled openness to supporting the resolution if it is amended to preserve self-defense authorities for forces already deployed, according to two GOP aides familiar with the discussions.

The White House, for its part, has begun adjusting its message. White House Press Secretary Karoline Leavitt declined Monday to repeat the administration’s earlier line that the strikes inside Iran were fully covered by existing Article II authorities and 2001 authorization for the use of military force. Instead, Leavitt said the administration was “in good-faith conversations with Congress about the appropriate vehicle for ongoing operations” and was reviewing the appropriations committee’s conditions “carefully and with respect for the committee’s prerogatives.”

Vice President JD Vance, who has emerged as the administration’s principal interlocutor with skeptical Senate Republicans, spent Sunday evening in a series of phone calls with lawmakers whose support for the supplemental was wavering. A person familiar with the calls said Vance had told at least two senators that the administration would not oppose committee-level conditions on the supplemental so long as the underlying funding moved on its current timeline.

Hovering over Monday’s appropriations vote was an unrelated but politically entangled set of deliberations a few corridors away, where the Senate prepared for a cloture vote later in the day on the Sanders-Ocasio-Cortez artificial intelligence moratorium bill. Several senators in both parties said the coincidence of the two votes — one to fund a war, one to pause a domestic industry — had produced an atmosphere on the floor unlike anything they had seen in their tenures. “It feels like the Senate is being asked to decide what kind of country we are this week,” said Sen. Brian Schatz, D-Hawaii. “Both at once.”

Reema Khoury, a former Senate Foreign Relations Committee aide now at the Stimson Center, said the appropriations vote and the looming war powers fight marked the first real institutional pushback of the conflict. “Up until now, Congress has reacted. This week is the first time it is acting,” Khoury said. “Whether that holds depends entirely on whether the floor votes that come look like Monday’s committee vote.”

Senate aides said floor consideration of the supplemental was tentatively scheduled for Thursday or Friday, with the war powers resolution potentially following on a parallel track. Collins, for her part, said she expected “a long week.”