Homa Bay Governor Cyprian Awiti becomes the second county boss to have his victory nullified following High Court ruling on Tuesday.
Last month, Wajir Governor Mohammed Abdi become the first sitting governor to lose his seat following a Nairobi court ruling.
And on Tuesday in Homa Bay, former Kasipul MP Oyugi Magwanga had the High Court ruling in his favour after months of battle in court.
Justice Joseph Karanja found that that the elections were not conducted in a free, fair and verifiable manner thus giving room for a by-election.
Oyugi had sued Governor Awiti, Deputy Governor Hamilton Orata, IEBC and the County Returning Officer Michael Kosgei.
In November, Justice Karanja ordered vote scrutiny for all poll returns and KIEMS technology deployed during the election.
The two leaders had their first dwell during ODM primaries in April last year in which Awiti managed to secure a controversial victory.
Later, Oyugi ditched the ODM party and contested as an Independent candidate and subsequently lost narrowly in August elections.
According to the results published by IEBC in August, Awiti garnered 210,173 votes while Magwanga managed 189,060 votes. Jubilee candidate Tom Onyango scored 1,432 votes.