Orange Democratic Movement (ODM) Secretary-General Edwin Sifuna insists Building Bridges Initiative (BBI) report's recommendation will sail through.
President Uhuru Kenyatta is set to receive the report on Tuesday in State House, with public launching expected a day later at the Bomas of Kenya.
A section of politicians has vowed to oppose the report while those leaning to Uhuru and Raila Odinga have maintained that it will be implemented.
Over the weekend in Kitui, Edwin Sifuna said he will ensure Western Kenya support the report.
He said he will work together with Kakamega Senator Cleophas Malala and nominated MP Godfrey Osotsi to deliver.
"As a party, we are all doing well. We gave birth to Handshake combined in Kibra. Sifuna is there, Malala is there, Osotsi is also there. We are ready to take the mantle in Western. When I agree with BBI, all Luhyas will pass it," Sifuna said.
The three youthful leaders have become Raila's voice in Western Kenya following the fallout between the ODM leader and his lieutenants Musalia Mudavadi and Moses Wetangula.
On Sunday in Kakamega, Governor Wycliffe Oparanya defended Malala and Osotsi following increased pressure from Mudavadi's ANC to have them quit.
"The wrangles in other parties, ODM cannot be part of them. When I see young men like Osotsi and Malala, who should take leadership from us are under siege, I welcome them to ODM," Oparanya said.
"I have no problem. I am the party leader and I will welcome you there. We must work for the people," added the county boss, a key pointsman for Raila Odinga in Western Kenya.
It's anticipated that BBI will recommend for constitutional changes which could subject the country to yet another referendum before 2022.