Mr Raihania said he expected Dr Sharples would be retained by the party in another role.
"Every party goes through some kind of change and parties need to be refreshed and rebranded. Labour is going through that now," he said. "No party can stay the same forever and Dr Sharples has been very responsible in his decision."
Mr Raihania said his final decision on whether to stand again would be determined by feedback from his whanau.
The Maori Party will hold its annual party this month.
Whether the party's rebrand includes some form of merger with the Mana Party would be on the table at the annual meeting.
A Mana Party spokesperson said the party was awaiting the outcome of the Maori Party's annual meeting and the possibility of "sitting down and having a talk".
"If ever there was a strong message for the two parties to come together, it was delivered when the Ikaroa-Rawhiti by-election results came in. Mana and the Maori Party combined would have beaten Labour and our people are calling for unity, not division."