Former Embu Senator Lenny Kivuti filed a petition challenging the re-election of Mr Martin Wambora as governor.
Mr Kivuti submitted the 1,000 page document at the Embu High Court.
Mr Kivuti is represented by Prof Tom Ojienda, Mr Wilfred Nyamu, Mr Daniel Kamunda and Mr Kirimi Guantai.
Mr Wambora of Jubilee Party was declared winner in the August 8 poll after garnering 97,760 votes against Mr Kivuti’s 96,775.
However, Mr Kivuti claims electoral malpractices were perpetuated to hand Mr Wambora the win.
The petition will be mentioned on Tuesday.