Among the structures that devolution came up with was the creation of the offices of senators and governors. The two were to perform distinct but somewhat interlocked functions in the new governance structure that took services closer to the people. While the governor's role is to oversee the running of their respective counties with executive authority over certain functions (without reference to the national government), senators act as the link between the national government and county governments. They also play an oversight role over governors in the management of county funds.
From the outset, not many people, least of all the legislators, understood how devolution worked. It was a new concept that was being experimented with; the pros and cons of it still unknown. That uncertainty is what led some to vie for the senator seat while others opted for the governor's seat. As devolution took root, it became apparent which side of the bread in the devolved governance structure was buttered. In fact, the Senate and the National Assembly have been at loggerheads most of the time, fighting over who should do what. Evidently, the Senate has been the unlucky one. The National Assembly enjoys more say and power on critical matters that impact on the country.