ODM has warned its rivals against using party leader Raila Odinga's name in their attempts to win votes ahead of the senatorial by-election.
The seat fell vacant after the death of former Migori senator Ben Oluoch. Official campaigns are expected to end on October 5.
Party officials threatened to sue candidates from other parties who have used Raila on their campaign materials.
County party chairman Philip Makabong’o also warned those using 'Baba', Raila's nickname, on their campaign posters that they risked legal action.
"Only the party's candidate, Ochillo Ayacko, is allowed to use the name or image or our party leader," said Makabong’o.
He claimed Ayacko’s rivals had printed campaign materials "with 'Baba' prominently inscribed on posters, T-Shirts and billboards".
"We will not allow them to use our party's leader's name or even the nickname to confuse the voters," said Mr Makabong'o.
Federal Party of Kenya candidate Eddy Oketch has two billboards in Migori Town with words 'Wote ni wa Baba”.
Peter Jobando, the Green Congress Kenya candidate, has also designed his posters with the word ‘Baba’ on them.
Makabong’o, speaking to The Standard in Migori town, said they would write to the electoral commission to have rival candidates using the name 'Raila' cited for electoral offences and possibly disqualified from the race.
“We are aware some aspirants have been using ODM and the name of our party leader to seek votes. We are watching them. No candidate should include Raila’s image in his posters,” he said.
Mr Oketch, who vied for the same seat last year and finished second, could not be reached for comment.
However, Jobando dismissed the threats, saying; "It is absurd for the name ‘Baba’ to be associated with the former PM. ‘Baba’ may mean my biological father,” Jobando said.