Mr Peter Jobando, the Green Congress of Kenya candidate, has also designed his posters with the name ‘baba’ inscribed next to his initials.
Meanwhile, the killing of Rongo University student Sharon Otieno has added a twist to the senate seat race, with leaders allied to ODM using the incident to castigate Mr Obado, who had declared his opposition to Mr Ayacko’s candidature after the Orange party handed him a direct ticket.
Mr Obado shifted his support to Mr Oketch after former MP Dalmas Otieno withdrew from the race.
Mr Oketch's supporters have complained that ODM politicians from the county are using Ms Otieno’s killing as a campaign tool.
"It's true the incident is a major setback to our campaigns because Mr Obado will now concentrate on clearing his name and it's true he has lost some moral ground," said an ally of Mr Oketch, who asked not to be named because of the sensitivity of the matter.
"We were really banking on his massive grassroots networks and of course his deep pockets," he added.
Other candidates in the race are businessman Jobando Peter (Green Congress Party of Kenya), Mr Ogolla Dickson (Independent), Mr Otieno Samwel (Independent), and Mr Samuel Hodo (PDP).