Workers at the U.S. Agency for International Development are bracing for a loss of its independent status and sweeping layoffs as President Trump continues slashing foreign aid.

A sense of crisis among aid groups was growing as U.S.A.I.D.’s website went dark.

With two G.O.P. senators opposed, Pete Hegseth, President Trump’s pick for defense secretary, can afford to lose only one more. If he is confirmed, it is likely to be by the smallest margin for that post in modern times.

Samantha Hegseth is contractually obligated not to speak ill of him, according to the terms of their divorce. A former sister-in-law has said Pete Hegseth was threatening and abusive toward Samantha Hegseth.

All but two Republicans voted to advance Pete Hegseth’s nomination as secretary of defense to a final vote, as Democrats raced to bolster fresh allegations about his personal conduct.

A woman once married to the brother of Pete Hegseth, the defense secretary nominee, submitted a sworn statement to the Senate in a late-hour complication to his confirmation. His lawyer denied her account.

Scores of Democrats joined Republicans in approving the measure, even though existing law already allows immigrants with contested legal status who are convicted of sex crimes to be deported.

Mr. Rubio expressed views aligned with those of most senators who work on foreign policy, while taking care not to break from Donald J. Trump’s unorthodox ideas.

Representative Michael R. Turner, Republican of Ohio, had at times been critical of the president-elect. He told people that he was axed after an edict from Mar-a-Lago.

The Iowa Republican’s decision dramatically increases the likelihood that Mr. Hegseth will have enough votes to be confirmed as President-elect Donald J. Trump’s defense secretary.

Pete Hegseth, President-elect Donald J. Trump’s choice to lead the Pentagon, rejected what he said were “false claims” about his conduct.

The committee’s Republican chairman and its top Democrat were briefed on F.B.I. findings into Pete Hegseth, Donald Trump’s defense secretary pick. Democrats questioned whether there were gaps.

Democrats are demanding that Republicans slow consideration of picks for the new administration until they can review background checks, as the G.O.P. faces major pressure to quickly confirm them.

Most Democrats joined Republicans in voting to take up the measure, which would require the detention and deportation of undocumented immigrants charged with minor crimes.

The action put the measure on track for likely enactment given strong support for it among Republicans, who now control the Senate, and President-elect Donald J. Trump.