Randy DeValk, Majority Leader Harry Reid’s deputy chief of staff for legislative policy, will leave the Senate after serving for more than two decades.

DeValk, a longtime Senate aide who has served in his current role since 2005, is the latest senior staffer to announce his departure from the Nevada Democrat’s office in the past few weeks.

Prior to leading Reid’s policy team, DeValk worked as a senior policy adviser to former Majority Leader Tom Daschle (D-S.D.).

“Many Senate Democratic leaders and Senators have relied heavily on Randy’s expertise and guidance on virtually every major policy issue during his 24 years in the Senate, including 16 years in the Democratic Leader’s office,” Reid said in a statement Friday night. “While I had hoped his service would continue for the 112th Congress, I understand his decision to leave. Words can’t express how much I appreciate his hard work. I sincerely wish him the best as he opens the next chapter of his life.”

Bill Dauster, who most recently served as deputy staff director and general counsel for the Finance Committee, will replace DeValk in Reid’s policy shop.

Reid shook up his senior staff shortly after Democrats lost six seats in the November elections, putting former Chief of Staff Gary Myrick in as lead floor director of the majority for the Democratic caucus and elevating Deputy Chief of Staff David Krone to chief of staff. Longtime Reid aide David McCallum will continue in his role as the Majority Leader’s deputy chief of staff.