Azimio leader Raila Odinga has arrived at Moi Stadium Kisumu in Kisumu where the rally is taking place.
He was accompanied by Narc leader Martha Karua, Wiper leader Kalonzo Musyoka and other leaders affiliated with the party as the crowd welcomed him in praise.
Raila had first held a consultative forum with leaders from Nyanza before the rally.
Residents came in numbers to the rally as they got entertained by different kinds of songs before it officially began.
The ODM leader made a triumphant entry to the lakeside city to a warm reception by hundreds of his supporters.
Present were Jubilee secretary general Jeremiah Kioni, Kisumu Governor Anyang' Nyong'o, Homa Bay Governor Glady's Wanga among others.