The Orange party has convened the National Delegates Convention (NDC) to endorse its presidential candidate.
The ODM party delegates will meet at the Kasarani Stadium gymnasium, a week after the National Super Alliance (NASA) where Raila is a principal, unveils the joint Opposition candidate.
The meeting is slated for May 4, according to a notice issued by acting secretary general Agnes Zani.
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"The acting Secretary General of the ODM party Senator Agnes Zani has issued notice for the NDC of the party to be held at the Moi International Sports Centre, Kasarani gymnasium in Nairobi starting 9am," a statement from Orange House said Sunday.
The meeting will bring together all members of the National Executive Committee (NEC), all chairpersons of the branch executive committees (mainstream), all sitting ODM MPs, governors and deputy governors.
It will also bring on board national officials of the ODM women league, youth league, the National Elections Board, majority and minority leaders of county assemblies, all chairpersons of party's standing committees and all chairpersons of county co-coordinating committees.
"The main agenda will be the nomination of the ODM presidential candidate," the notice adds.
The ODM meeting will be a formality as the law requires that the NDC, the supreme organ for the party, endorses or ratifies the nomination of a presidential candidate.
In the past, such a meeting has been used to pick a flag bearer but this time it will only be to endorse one who will have been picked by the five NASA principals.
The other NASA affiliates - Chama Cha Mashinani (CCM) and Ford Kenya - too are expected to convene their respective NDCs to endorse their candidate.
Amani National Congress (ANC) and Wiper party have already endorsed Musalia Mudavadi and Kalonzo Musyoka respectively.
On Thursday, Raila, Kalonzo, Mudavadi, Wetang'ula and Bomet Governor Isaac Ruto met delegates and aspirants at the Bomas of Kenya. They promised to unveil their line-up on Thursday at a major rally at Uhuru Park, Nairobi, while announcing the return of the 2007-like Pentagon.
In 2007, Raila teamed up with Mudavadi, William Ruto, Joe Nyagah, Najib Balala and Charity Ngilu to form the Pentagon.
