The staff shakeup comes in the middle of a year that saw the NRSC consistently lagging its Democratic counterpart in fundraising.
Though the GOP committee has paid down its debt and the Democratic Senatorial Campaign Committee is still more than $10 million in the red, the DSCC outraised the NRSC nearly every month this year and by more than $10 million overall.
Carson will remain on the committee's payroll and will continue to engage in direct donor outreach.
"Shelly is a valuable member of our team whose strength and skill is working directly with donors, and will focus directly on fundraising efforts instead of day-to-day operations," NRSC Communications Director Brad Dayspring said.
Heather Larrison, president of the D.C.-based firm The Larrison Group, will assume Carson's operations and management duties with the committee.
A source familiar with the staff movements emphasized that that the committee is merely shifting people to better utilize their strengths.