President Joe Biden on Wednesday nominated Summer Mersinger and Caroline Pham to fill two Republican spots on the Commodity Futures Trading Commission, the White House said. Mersinger most recently served as chief of staff to CFTC Commissioner Dawn Stump and previously served as a top aide to Republican Senator John Thune. Pham is a managing director at CitigroupInc (C.N) , where she has worked since 2014, according to her LinkedIn profile. She also previously served at the CFTC as a policy adviser to former Republican Commissioner Scott O"Malia. If confirmed by the Senate, the pair will help fill out a depleted CFTC where the five-member board currently has only two members. Stump, the derivatives regulator"s lone Republican, said earlier this month she would not seek another term but would remain until new officials join. The regulator is currently led by acting Commissioner Rostin Behnam, whom Biden has also nominated to lead the watchdog on a full-time basis. Reporting by Caitlin Webber; Editing by Tim Ahmann and Peter Cooney Our Standards: The Thomson Reuters Trust Principles.