Nairobi Senator Johnson Sakaja, Governor Mike Sonko and former governor Dr Evans Kidero are Nairobi county's top politicians who won elective seats on their first attempt.
Before contesting for an elective seat, Senator Sakaja was the chairman of the defunct President Uhuru Kenyatta's led The National Alliance (TNA) party from 2013 to 2017.
TNA was formed in the run-up to 2013 general elections and was dissolved together with other political parties in 2017 to form the ruling Jubilee party.
Sakaja ran for Nairobi county's senatorial seat in 2017 on a Jubilee ticket and won with 832,841 votes.
Governor Mike Mbuvi Sonko entered politics for the first time in 2010 when he contested for Makadara by-election seat and won with 19,913 votes on a Narc Kenya ticket.
He subsequently won Nairobi senatorial seat with more than 800,000 votes.
In 2017, Sonko ran for Nairobi gubernatorial seat on a Jubilee party ticket and beat his rival Dr Evans Kidero with 871,794 votes.
"Amongst the senators, Nairobi’s John Sakaja (832,841) and Kiambu’s Kimani Wamatangi (732,625) had the highest number of votes," noted a 2017 general elections Daily Nation report.
Dr Evans Kidero contested for Nairobi gubernatorial seat on an Orange Democratic Movement (ODM) ticket and won in 2013.
He consequently won with 692,483 votes and became the first governor of Nairobi under devolved government.
Later in 2017 general elections, Kidero lost his gubernatorial seat to Mike Mbuvi Sonko, the former and first senator of Nairobi county.