Schumer, who wants to see the defense bill pass before senators leave for August, has warned against “toxic” amendments that could tank the package.

Chief among those are measures related to the Pentagon’s policy to provide leave and travel reimbursement for troops who cross state lines to seek abortions.

The issue has ground the normally expeditious confirmation of top military promotions to a halt as Sen. Tommy Tuberville (R-Ala.) jams up the process in a bid to force the Pentagon to reverse the abortion policy. The logjam has ensnared nearly 300 generals and admirals, including President Joe Biden’s pick to be chair of the Joint Chiefs and the top officers in the Army and Marine Corps.

Schumer has offered Tuberville an abortion vote to break the impasse. But Tuberville said that’s not good enough, instead insisting the Pentagon first rescind its policy, which he argues skirts laws that ban federal dollars for most abortions, before holding a vote to turn the policy into law.

“As I’ve told them, ‘Change it back and then let’s vote,’” Tuberville told reporters.

“I’m getting to the point now where [the] next vote we’re gonna have on these nominees, it’s gonna be after we vote on a bill that will codify what they’ve got,” Tuberville said. “But we’ve got to change the policy backwards before we vote on it.”

Adding abortion language — either through a GOP effort to restrict the policy or Democratic counterproposals to codify it — would make it nearly impossible for the Pentagon policy bill to achieve the votes needed to clear the Senate.

Sen. Roger Wicker of Mississippi, the top Republican on the Armed Services Committee, predicted that the abortion policy debate won’t happen as part of the defense bill.

The situation is a contrast with the House, where Speaker Kevin McCarthy’s narrow majority has forced him to cater to conservatives who can threaten his speakership. McCarthy granted votes on a variety of conservative measures that were added to the bill, marking a hard right turn that saw almost all House Democrats oppose the bill.

In the Senate, the 60-vote threshold means any legislation must have bipartisan support to pass, and renders most of those proposals dead on arrival.

But even if the Senate skips a vote, the issue over abortion access isn’t going away. The House’s version of the defense policy bill would undo the policy, a non-starter with Democrats that will need to be dealt with when the two chambers try to strike a compromise on their competing versions.

The House GOP bill is packed with other hard-right provisions that won’t fly in the Democratic-led Senate, including restrictions on transgender medical care and significant limits on Pentagon diversity and equity programs. Senate Republicans did, however, win some provisions to rein in diversity efforts.

The Senate voted on 13 mostly uncontroversial standalone defense amendments last week, compared to none in the previous two years. But other fights could test that progress.

Debates could emerge on authorizing defense spending, either on GOP efforts to increase the bill’s $886 billion topline or progressive proposals to slash the Pentagon budget. Conservatives could also push amendments to more significantly limit Pentagon diversity, equity and inclusion efforts.

Another question is whether Schumer and Democrats will mount a fight to approve the transfer of nuclear submarines to Australia after Wicker blocked an attempt to include language in the bill. The move is a cornerstone in the AUKUS sub pact Biden struck with Australia and the U.K. and needs a green light from Congress.

Wicker and other defense hawks say they want supplemental funding first, arguing the U.S. can’t build enough subs for both countries without more money to ramp up the industrial base. But a fight could be tough for Democrats from shipbuilding states who may agree that more money is needed to manufacture subs.

Schumer locked in a pair of votes targeting China when the Senate returns Tuesday. The chamber will vote on Sen. John Cornyn’s (R-Texas) amendment to scrutinize U.S. companies’ investments in certain Chinese tech industries, and an amendment from Sens. Mike Rounds (R-S.D.) and Jon Tester (D-Mont.) to ban China, Russia, Iran and North Korea from buying U.S. farmland.

Any single senator who feels shut out could still halt the process by objecting to votes on all other senators’ amendments. Those disagreements have torpedoed Senate debate on the defense bill in past years, but leaders have sidestepped that scenario so far.

Joe Gould contributed to this report.