The Independent Electoral and Boundaries Commission has declared Mutula Kilonzo Jnr the duly elected Makueni Senator.
Makueni County Returning Officer Salad Boru said Mr Kilonzo Jnr had garnered 163,232 votes against his nearest challengers Philip Kaloki of the National Rainbow Coalition (Narc) (9,762) and Party of Independent Candidates of Kenya's Harun Mwau (6,431).
"I, Salad Boru, the Makueni County Returning Officer hereby declares Mutula Kilonzo Jnr as the duly elected Senator of Makueni County," Mr Boru said to ululations from Mr Kilonzo Jnr's jubilant supporters.
Other candidates in the race, Urbanus Katumo, an independent candidate, managed 517 votes while Jane Kitundu of the Labour Party of Kenya got 387 votes.
Mr Boru said the total votes cast were 180,329 while rejected votes stood at 619.
He said the total registered voters in the County were 298,474.
Turnout was 60.42pc, said the IEBC official.