Matovu, the former occupant of Bukanga parliamentary seat succumbed to throat cancer at Nakasero Hospital in Kampala, last month.
Recently, President Yoweri Kaguta Museveni rushed to Bukanga to campaign for NRM flag-bearer, Stephen Rwakanuma Kangwagye, ahead of today’s by-elections.
Museveni showed his support for Kangwagye by assuring Bukanga voters that the NRM is still determined to extend social services to Isingiro.
The Electoral Commission chairman, Eng Dr. Badru Kiggundu, on Friday released the programme for the election; saying that at least seven contestants were nominated for the position.
He further warned voters not to mar the process by engaging in unnecessary quarrels as has been the case.
Meanwhile, one of the contestants, Jacqueline Asiimwe Matovu has been confirmed to have bowed out of the race at the last minute.
Reasons for her quiting remain unclear.
The rest of the group includes Nathan Byanyima, Jeremiah Kamurali Birungi and Humble Abel Tumusiime as independent candidates.
The actual showdown is between Kangwagye who is representing NRM and Turiyo Tito, the flag bearer for FDC.
As directed by Kiggundu last Friday, campaign meetings ended on November 24 2013.
The commission dispatched polling kits on Sunday to ensure polling materials are distributed to all the 135 polling stations in Bukanga before 7.00am today.
Voting kicks off this morning.