The U.S. Senate confirmed Texas Sen. Brian Birdwell to serve as an assistant secretary of defense on Monday, a return to the Pentagon for the five-term Granbury Republican.

Birdwell was confirmed on a 46-43 vote in the Senate alongside several dozen other nominees. He previously worked as staff for the Department of the Army at the Pentagon, where he suffered severe burns during the Sept. 11, 2001, terrorist attacks when a plane crashed yards away from his office.

Birdwell announced in June that he would not seek reelection to Senate District 22, where he has served for 15 years. The White House announced Birdwell’s nomination in October.

In a statement, Birdwell thanked his constituents and Texas’ U.S. Sens. Ted Cruz and John Cornyn for assisting with his nomination through committee and full Senate.

“Let me again thank you for the privilege and honor of serving you for nearly 16 years in the State Senate,” Birdwell said. “I ask your prayers for my future duties and that you keep our next state senator in your prayers for wisdom as they serve the district.”

State Rep. David Cook, R-Mansfield, is running to replace Birdwell after decisively winning the Republican party nomination for the seat in March. He will face off against Democrat Amy Martinez-Salas, a first-time candidate, in November.