WASHINGTON ― Senate Republicans on Tuesday introduced a governmentwide, $1.4 trillion spending package, with $696 billion for defense, teeing up negotiations in Congress’ tense lame-duck session ― and several fights with House Democrats.

The government is operating on a stopgap continuing resolution, or CR, through Dec. 11, and Congress must either pass a deal, or another funding patch, to avoid a government shutdown in the middle of a turbulent presidential transition. A separate COVID-19 relief effort and the annual defense policy bill are also on Capitol Hill’s busy to-do list.

The Senate must reconcile its long-awaited package of 12 bills with the House, which passed its own bills in July. The Senate’s GOP-drafted defense language for fiscal 2021 differs from the House version on the number of Lockheed Martin-made F-35 Joint Strike Fighters to order and funding for a space-based sensor.

Compared to the House bill, the Senate version also calls for one fewer Virginia-class submarine and $19 million more in funding for next-generation 5G networks.

Though the Senate bill was mostly bipartisan and Senate Appropriations Committee Chairman Richard Shelby, R-Ala., expressed confidence in an eventual deal, the atmosphere for compromise is unclear. The post-election period remains white hot politically, as Republican leaders back President Donatl Trump in his legal challenges of President-elect Joe Biden’s electoral win, and as two races to determine control of the Senate face January runoffs.

On Tuesday, Democrats chided Republicans over the long-stalled bills. Stopping short of endorsing the effort, Senate Appropriations Committee Vice Chairman Patrick Leahy, D-Vt., criticized the legislation for ignoring the country’s COVID-19 relief needs, shortchanging safety net programs and the environment, and wasting money on Trump’s border wall.

The House passed its $694.6 billion Pentagon spending bill for fiscal 2021 in July as part of a $1.3 trillion package. It included politically charged provisions to set aside $1 million for the Army to rename 10 bases that honor Confederate leaders and to bar the Trump administration from using more Pentagon funds on border wall construction. It would reduce transfer authority from the requested $9.5 billion to $1.9 billion, and place additional oversight mechanisms on the Defense Department’s ability to reprogram funds.

Here’s what stood out in the Senate GOP’s latest proposal:

Air warfare: The Senate panel would fund a total of 96 F-35s in FY21, 17 jets more than the Pentagon’s request and five more than the panel’s House counterpart. Its bill added about $1.7 billion for 12 F-35As for the Air Force and five F-35Cs for the Marine Corps and Navy.

Though the bill fully funds the B-21 bomber program, many of the Air Force’s other major development programs received slight cuts. Funding for one of its biggest priorities, the Advanced Battle Management System, shrank from $302 million to $208 million. The committee cited “poor justification” as a reason for the cuts.

The Air Force’s Next Generation Air Dominance program also would take a hit despite the headline-grabbing first flight of a full-scale demonstrator aircraft, which was disclosed by the service in September. The Air Force wanted $1 billion in FY21 to continue development of NGAD ― a suite of manned and unmanned air superiority technologies that could include a sixth-generation fighter. However, the committee shaved about $70 million off the request.

Naval warfare: The bill provides money to buy nine ships, though some argue it’s only eight because the LPD-17 was already procured. The total comes to roughly $21.35 billion, or $1.44 billion more than the president’s request, but less than the House bill.

The ships include one attack submarine (one less than the House bill but a match to what the administration requested), a Constellation-class frigate, two destroyers, and two towing and salvage ships.

The Senate bill also calls for nine P-8A Poseidon maritime patrol aircraft and four E-2D Advanced Hawkeyes, as well as 24 F/A-18 Super Hornet fighters.

5G technology: The bill fully funded the Pentagon’s $449 million budget request for defensewide 5G projects, $19 million more than the House. In their budget justification, House appropriators cited “historical underexecution” for its $430 million recommended allocation. The Pentagon is working with industry on multiple ongoing 5G experiments that are underway at military bases across the country. The department recently awarded $600 million in contracts for the effort.

Satellites: The bill also adds to frustrations expressed by members of the House at how a new constellation of hypersonic weapon-tracking satellites will be funded. While technically a Missile Defense Agency program, former Under Secretary of Defense for Research and Engineering Mike Griffin pushed for the Hypersonic Ballistic Tracking Space Sensor, or HBTSS, to be funded through the Space Development Agency.

Leaders of both agencies have insisted that the program remains under MDA’s ownership, but legislators have expressed concern over the arrangement and the low level of funding set aside for it. No money was set aside for HBTSS in MDA’s budget, while the Space Development Agency’s budget included $20 million for the critical sensor.

In June, the House Armed Services Committee’s' strategic forces subpanel threatened to transfer MDA away from the undersecretary of defense for research and engineering, placing it instead under the undersecretary of defense for acquisition and sustainment. While the Senate bill doesn’t go that far, it does add an additional $140 million in unrequested funding for HBTSS, including a $20 million transfer from the Space Development Agency. Furthermore, senators demanded the agencies report on their acquisition strategy for HBTSS and fully fund the program in their future budget proposals.