Eight aspirants hoping to win the Baringo South parliamentary seat are expected to battle it out in the Jubilee Party nominations.
The seat fell vacant following the death of Grace Kipchoim in April from cancer.
Five candidates have already formally expressed their interest in the June 14 nominations, tipped to be more tightly contested than the August 17 by-election.
“There’s a huge power struggle for the party ticket," said Amos Lempaka, one of the aspirants who defected from Orange Democratic Movement party to Jubilee recently.
Others who will contest the ticket are Charles Kamuren, Lewis Megiri, Mark Kibenei, Joseph Tarus and Dickson ole Keis.
Speaking in Marigat after meeting the aspirants, Deputy President William Ruto told voters that the party had no preferred candidate.
He said the aspirants' fate during the primaries would be in the hands of the electorate, who would pick the party's flag bearer.
But some of the Jubilee aspirants expressed fears that three recent defectors might have the upper hand.
"We have seen people defecting to Jubilee; they should not expect to be favourites because they have joined Jubilee. Let all candidates face the electorate,” Mr Kibenei said.
Mr Lempaka said he was not joining Jubilee because he needed favours but to seek an opportunity to serve the people of Baringo South.
“What matters most in politics is the interests of the people being catered for. We can't be campaigning and asking for votes when people are displaced by bandits, with IDP camps being the only place they call home," said Lempaka, who was among defectors received by the DP at Ng'ambo Secondary School.
Mr Kamuren, who was second after Ms Kipchoim in the August 8 General Election, promised to serve the people if he was elected.