Last-minute closed-door talks between Senate Republicans and Democrats failed to prevent a "nuclear option" in the upper chamber, as frustrations on both sides killed a deal to move ahead with President Donald Trump’s nominees.  

Lawmakers were inching closer to a deal that would have allowed sub-Cabinet-level nominees to be voted on in bunches, but neither side could reach a final agreement.

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Senate Republicans argued that a majority of their counterparts agreed with the new proposal, but that Senate Minority Leader Chuck Schumer, D-N.Y., was still standing in the way.

"I think the majority of Democrats are on board with it," Sen. James Lankford, R-Okla., told Fox News Digital. "And Schumer is blocking it from actually having consent to come to the floor."

The failed deal was a modified version of a proposal first unveiled by Senate Democrats in 2023, and would have allowed 15 nominees to be batched together en bloc and voted on while still requiring two hours of debate for the group.

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But when Lankford brought the proposal to the floor for consideration, Sen. Brian Schatz, D-Hawaii, blocked it.

Schatz argued that Senate Republicans were trying to rush through the negotiating process ahead of their plan to leave Washington for the weekend.

"What they're asking for is unanimity, and we don't have it," he said. "And so, if you're interested in enacting this on a bipartisan basis, the process for doing that — It is available to you. But again, it's more a matter of running out of patience than running out of time."

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Senate Majority Leader John Thune, R-S.D., fired back "how much time is enough?"

"Give me a break," he said. "Two years. Not long enough. How about eight months? Eight months of this."

With the prospects of bipartisan deal to move nominees through Democrats' blockade, Senate Republicans are expected to continue down the path of the "nuclear option."

That means that their initial proposal, which would allow for an unlimited number of sub-cabinet level nominees to be voted on en bloc with 30 hours of debate tacked on, is expected to pass with a simple majority, and effectively change the confirmation process in the Senate.

"We are achingly close to doing this like adults," Schatz said.

The gun recovered by authorities in the assassination of Charlie Kirk was a bolt-action rifle — a common hunting weapon valued for its reliability but limited to a single shot before reloading.

Unlike a semi-automatic, the shooter must manually operate the bolt handle to cycle the weapon: lifting and pulling it back moves the spent cartridge, while pushing it forward chambers a new round from the magazine. Lowering the bolt locks the round and seals the chamber, making the rifle ready to fire again — a simple, durable design that has kept it popular among hunters and target shooters.

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"This process limits the rate of fire, you can only take one shot at a time," explained Retired Marine Lt. Col. Hal Kempfer in an interview with Fox News Digital.

Kempfer noted that with a bolt-action rifle, the spent cartridge often remains in the chamber rather than being ejected, meaning shooters don’t leave behind shell casings or "brass" that investigators can use for forensics.

"That's just one of those things where you, if you've thought it through, you know that you can't leave any forensic evidence for investigators to work with," he said.

On Thursday, authorities said they recovered the rifle used to assassinate Kirk in the woods near the scene, where investigators believe the shooter abandoned it while fleeing to evade law enforcement.

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"They're gonna be doing a lot of work on the forensics of this weapon as these firearms tend to have a history," he said, adding that investigators will try to trace where it was sold and how it changed hands. 

"It’s possible the shooter used a straw buyer or another method to conceal their identity — but that’s the kind of legwork investigators will now have to do to track the shooter," Kempfer said.

Kempfer, who served as an intelligence officer in the U.S. Marine Corps, said that the fatal shot was "not a particularly difficult" one but does take planning.

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"You wouldn't have to be some expert sniper or something, hunters take this shot all the time," he said, adding that the distance, clear weather, and elevated position all worked to the shooter’s advantage.