McDonald is a member of the African National Congress.[1] He was 8th on the party's regional Free State election list for the general election of 8 May 2019.[2] Following the election, he was sworn in as a Member of the National Assembly on 22 May 2019.[1] McDonald became a member of the Portfolio Committee on Transport on 27 June.[1]
On 2 July 2019, he nominated Mosebenzi Zwane to become chairperson of the transport committee.[3]
McDonald did not stand for reelection in the 2024 general election.[4]