McCue had been serving for the last year as president and CEO of the ONE Campaign, the non-profit organization dedicated to fighting global poverty. McCue is stepping down on Dec. 1 to open her communications and consulting firm. She will remain as a consultant for ONE, in addition to going back to work for Reid.
"Candidates and voters are talking about ending extreme poverty, saving millions of lives and building a more secure future with America leading the way. The groundwork has been laid for a great march onward," McCue said. "The past year at ONE has been an amazing journey and I eagerly look forward to advancing the mission."
McCue was Reid's longtime chief of staff before leaving for the ONE Campaign, and she helped build that organization from scratch over the last year. U2 front-man Bono, as well as Microsoft CEO Bill Gates and investor Warren Buffett are involved in ONE.