The BBI secretariat has announced that it has realised 5.2 million signatures in support of the referendum.
The number of referendum backers could go as high as six million signatures of registered voters by the end of the day, the secretariat team projects.
The details of the signatures collected were unveiled on Friday at the Building Bridges Initiative secretariat led by opposition chief Raila Odinga.
BBI co-chair Dennis Waweru said the signatures will be submitted to the Independent Electoral Commission in the next one week for verification.
"We have already put in places a digital mechanism to capture the signatures in the format approved by IEBC within the short time possible," the ex-Dagorreti South MP said.
According to Waweru, the signatures collection exercise has been completed without any hitches across the country, a demonstration of great goodwill from Kenyans.
The signatures were delivered to the secretariat from at least 16 regional coordinators who spearheaded the process.
Kisii and Nyamira regional coordinator Patrick Lumumba who is also the Kisii county secretary said during signature handover event that Kenyans are ready for a referendum.
"The good things contained in the report including more access to credit for the youth, empowerment of women and more resources to counties are just a few but many of the things exciting Kenyans," he said.
The signature collection exercise in support of the BBI referendum came to an end on Friday, ramping up the country to the next phase of verification by IEBC before the Constitution of Kenya Amendment Bill 2020 is submitted to assemblies for action.
