WASHINGTON — When Congress returns to Capitol Hill in September, lawmakers will face a massive to-do list on defense issues, including a stopgap bill to keep the government open through the midterm election, a supplemental funding plan to cover the Iran war, and the fiscal 2027 defense budget.

The Pentagon is betting big on a $1.15 trillion discretionary budget request with a further $350 billion coming from the reconciliation process — together adding up to a historic $1.5 trillion defense budget. But whether the Republican-led Congress can find the political will to pass the full $1.5 trillion sum is very much up in the air, with both chambers in various states of progress.

The House has yet to pass its version of the FY27 defense appropriations bill, having moved the bill through committee in June. But the Senate is even further behind, with Republican and Democrat leaders of the Senate Appropriations Committee still at a stalemate on how to balance defense and nondefense spending. As a result, Senate appropriators have not yet released the text of the FY27 defense spending bill.

That situation has had a trickle down effect on passing the National Defense Authorization Act. The House passed the NDAA in July, but Senate Democrats have prevented the upper chamber from bringing its version of the bill to the floor, with members citing the war in Iran and questions about the defense topline as key reasons for blocking the bill.