The U.S. Senate on Thursday confirmed Katherine Sutton to be the Defense Department's new cyber policy chief, filling a key vacancy after a slew of leadership departures.

Sutton becomes only the second individual to serve as the Pentagon’s assistant secretary of defense for cyber policy, an office that was established last year after congressional frustration that DOD lacked an accountable civilian leader for its digital plans and activities.

Senators voted 51-47 to confirm Sutton as part of an en bloc package of four dozen nominees for various federal agencies. The vote came after Republican senators deployed the "nuclear option" to alter the chamber’s rules in order to confirm President Donald Trump's picks faster.

Sutton most recently served as the chief technology adviser to the commander and director of Pentagon operations at U.S. Cyber Command. She previously held a number of roles for the Senate Armed Services Committee, including as the GOP staff leader for the cybersecurity subcommittee under Sen. Mike Rounds (R-SD).

There had been concerns that Sutton’s nomination would be scrapped because of her ties to former Cyber Command and NSA chief Timothy Haugh, who the president dismissed in April.

During her confirmation hearing in May, Sutton vowed to examine the Pentagon’s cyber capabilities to make sure the department is keeping pace with China and other digital foes.

“As I have watched the domain evolve over the last decade, it is very clear that our adversaries are becoming not only increasingly capable, but also increasingly aggressive in the domain,” she said.

Sutton inherits an organization that has seen its senior leaders depart in recent weeks. Laurie Buckhout, who has been performing the assistant secretary duties in an acting capacity, left the office earlier this month to pursue another role in the administration.

Buckhout, a retired Army colonel who ran for Congress in North Carolina last year as a Republican, was originally tapped to serve as the deputy assistant secretary of defense for cyber policy earlier this year. That post is still vacant.

In addition to Buckhout, Ashley Manning, who was the policy shop’s principal deputy and filled the interim chief role when it initially opened and after the change in administration, has been sent on a rotational assignment to the RAND Corporation.