Deputy President William Ruto on Wednesday officially endorsed Vivo Energy MD Polycarp Igathe as Mike Sonko's running mate.
Sonko and Igathe will contest the Nairobi governor post against incumbent Evans Kidero of ODM during the August 8 poll.
Ruto and Senator aspirant Johnson Sakaja hosted the two at Jubilee Party headquarters in Pangani.
There are reports that State House had a hand in Igathe being named running mate.
Ruto said the two are a dynamic duo who will win the Nairobi seat by a landslide.
"We are not playing a 50-50 game here. We are confident that with Igathe on board, the Nairobi chapter is closed."
The Senator settled on the Vivo MD on Tuesday instead of former Starehe MP Margaret Wanjiru who had been tipped as his choice.
The two on a pact that was to see Wanjiru named running mate after the Jubilee primaries.
Wanjiru battled it out with Sonko and former Gatanga MP Peter Kenneth at the nominations.
At that time, she claimed they had an arrangement with the legislator that whoever wins will name the other as running mate.
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The Star learned that President Uhuru Kenyatta had tasked trusted State House operatives to interview Sonko's running mates.
Sonko has rebranded himself as a thoughtful, calm, conservatively dressed candidate.
The President is said to have asked private secretary Jomo Gecaga and Solicitor General Njee Muturi to oversee the recruitment.
They settled on Igathe who is also said to be Jubilee's strategist and Uhuru's adviser on energy issues.
State House had offered Sonko a CS post to drop out and support the more 'respectable' Peter Kenneth.
Then there were sudden objections to his previously approved academic papers. To no avail. Sonko wouldn't cave.
Sonko said if he wins the seat, he will recover Sh 64 billion the national government owes Nairobi County.
He said the amount will be used to create jobs and clean up the city.
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