The APC candidate, Mr Gaya, challenged Mr Kawu at the election petition tribunal.
The National and State House of Assembly Election Petition Tribunal sitting in Kano has upheld the election of Kawu Sumaila of the New Nigeria People's Party (NNPP) representing Kano South Senatorial District.
The Independent National Electoral Commission (INEC) declared Mr Sumaila the winner of the Kano South senatorial election conducted on 25 February.
Mr Kawu won the senatorial election with 319,557 votes. He defeated Kabiru Gaya of the All Progressives Congress (APC) who scored 192,518 votes.
The APC candidate, Mr Gaya, challenged Mr Sumaila's victory at the election petition tribunal.
On Monday, the tribunal dismissed the petition by Mr Gaya for being grossly incompetent and fined him N200,000.
The chairman of the tribunal, R. Odogu, held that the petitioner failed to discharge the burden of proof against the respondent.
"We find no merit in this petitioner and accordingly hereby dismissed.
"We similarly affirmed the declaration of Abdulrahman Kawu Sumaila of NNPP as the winner of the Kano South Senatorial District election, held on 25th Feb. 2023.
"The sum of N200,000 cost is hereby awarded in favour of the respondents against the petitioner, the judge ruled.