U.S. President-elect Donald Trump’s nominee for Secretary of Defense Pete Hegseth testifies during his Senate Armed Services confirmation hearing on Capitol Hill on January 14, 2025 in Washington, DC. (Photo by Anna Moneymaker/Getty Images)

WASHINGTON — The Senate confirmed Pete Hegseth to be the next secretary of defense tonight by the narrowest of margins, with Republicans relying on a tiebreaking vote from Vice President JD Vance to clear one of Trump’s most controversial nominees after weeks of questions about his fitness to lead the Pentagon.

The nomination prevailed in a 51-50 vote after Republican Sens. Lisa Murkowski, Susan Collins and Mitch McConnell joined Democrats to vote against Hegseth.

Hegseth, a Fox News host and National Guard veteran, has faced a rocky road to the top defense job since being tapped by President Donald Trump to lead the Pentagon in November. In the following weeks, allegations of sexual misconduct and whistleblower reports alleging that Hegseth abused alcohol while on the job at Fox News and as the former president of Concerned Veterans for America threatened to topple his nomination. Hegseth has denied all allegations of sexual misconduct and has pledged to stop drinking if named secretary of defense. 

Although Hegseth’s nomination appeared to be on steady footing after his Jan. 14 confirmation hearing in front of the Senate Armed Services Committee, questions about Republican defectors arose after new allegations surfaced about Hegseth’s previous marriage. 

Senators received an affidavit Tuesday, a redacted copy of which was obtained by Breaking Defense, in which Hegseth’s former sister-in-law, Danielle Hegseth, claimed that Pete Hegseth’s aggressive behavior caused his second wife to fear for her safety and form an escape plan. Hegseth’s second wife, Samantha Hegseth, told NBC News — which was first to report on the affidavit — that there had been no physical abuse in her marriage, while Hegseth’s lawyer denied the allegations.

On Thursday afternoon, Alaska’s Murkowski became the first Republican to state she would vote against Hegseth, noting her enduring concerns about Hegseth’s judgement, his comments about women in combat, and questionable financial management of the veterans organizations he previously led.

“I believe that character is the defining trait required of the Secretary of Defense, and must be prioritized without compromise. The leader of the Department of Defense must demonstrate and model the standards of behavior and character we expect of all servicemembers, and Mr. Hegseth’s nomination to the role poses significant concerns that I cannot overlook,” she said in a statement on X, formerly known as Twitter.

Collins, who represents Maine, released a statement declaring her intent to vote against Hegseth shortly afterwards.

“While I appreciate his courageous military service and his ongoing commitment to our servicemembers and their families, I am concerned that he does not have the experience and perspective necessary to succeed in the job,” she wrote in a statement on X.

Both Murkowski and Collins on Thursday joined Democrats in voting against a procedural move to bring Hegseth’s nomination for a final vote, which succeeded 51-49.

However, questions swirled around whether McConnell and Sen. Thom Tillis of North Carolina, who both voted to advance the nomination on Thursday, would join Murkowski and Collins to vote against Hegseth during the final vote — potentially torpedoing Hegseth’s nomination.

Minutes after the final vote began, Hegseth posted his response to Danielle Hegseth’s allegations, addressed to Tillis, on X.

“I dispute Ms. Dietrich’s characterization of me as being abusive to my ex-wife Samantha or having an alcohol abuse problem,” Hegseth wrote, referring to his former sister in law. “I have been very open about how I have used alcohol in the past to deal with the demons that I experienced from my time in Iraq and Afghanistan, as countless of my fellow veterans have. However, this something I have overcome.”

“My ex wife Samantha has also been explicit in both court filings and in her public statement to NBC (and I believe her FBI interview) that were was no physical abuse,” he wrote later in the letter.

Shortly afterward, Tillis announced on X he would support Hegseth’s nomination.

“From the beginning, I have been clear about my position: if President Trump’s nominees were reported favorably out of the relevant committees, I would support their confirmation on the Senate floor absent new material information about their qualifications,” Tillis wrote. “Once Pete Hegseth’s nomination was sent to the floor by my colleagues on the Senate Armed Services Committee, I conducted my own due diligence, including asking tough questions of Pete and I appreciated his candor and openness in answering them.”

During Hegseth’s nomination hearing last week, Republicans praised Hegseth’s focus on readiness and lethality and repeated Hegseth’s claim that the allegations against him were baseless smears. Sen. Joni Ernst — a combat veteran and sexual assault survivor who was the most visible SASC Republican holdout on the nomination — announced hours after the hearing that she would support Hegseth’s defense secretary bid.

However, SASC Democrats hammered Hegseth about his comments on women in combat and said he didn’t meet the standards of character or job performance necessary to run the nation’s largest employer. 

SASC voted 14-13 along party lines on Monday evening to report the nomination out of committee.

In a floor speech on Tuesday, SASC top Democrat Sen. Jack Reed raised concerns about Trump’s firing of Coast Guard Commandant Adm. Linda Fagan earlier this week and said Hegseth’s confirmation could further destabilize the US military should he support efforts to purge military leaders who do not align with Trump’s politics. 

“Our servicemembers, since the birth of this country 249 years ago, have taken an oath to the Constitution,” Reed said. “Their mission is to protect the country and all of its citizens and the ideals this country was founded on, which should endure no matter who is President or what political party is in power. Mr. Hegseth’s idea of meritocracy, however, seems to be that servicemembers should pledge fealty to a President who will be in power for only four years and fit the ideas of a party that only half of this Nation supports. 

“There is no faster way to undermine the lethality and morale of our Nation’s military–and support of the Nation’s citizens for it–than to inject politics into the system,” he said. 

SASC Chair Roger Wicker, in a Thursday floor speech following Reed’s, said Hegseth had been a victim of a smear campaign and false media reports. He acknowledged Hegseth is an “unconventional” nominee, like Trump as president, but added that fresh ideas could shake up the Pentagon bureaucracy.

“That may be what makes Mr. Hegseth a good choice. He’s not beholden to the status quo and he’s open to new ideas,” he said. ”His experience in the line of fire and his servicemember advocacy make at least one thing clear. Pete Hegseth will put the men and women of our military first.”