From 1999 to 2002, and later from 2008 to 2014, he held several different portfolios in the Eastern Cape Executive Council under Premiers Makhenkesi Stofile, Mbulelo Sogoni, and Noxolo Kiviet.
During his first decade as a legislator, he rose to national prominence as a member of the left-wing coalition that supported Jacob Zuma's political rise; Masualle was the provincial chairperson of the South African Communist Party (SACP) in the Eastern Cape, and he served as the party's national treasurer from 2007 to 2012.
He was succeeded as provincial chairperson by Oscar Mabuyane at a hotly contested party conference, dubbed the "festival of chairs" for the violent brawl that broke out ahead of the vote.
Pursuant to the 2019 general election, he was sworn in to the National Assembly and appointed as a deputy minister by President Cyril Ramaphosa.
[6] In November 2002, the Mail & Guardian reported that the national ANC had ordered Premier Stofile to sack Masualle and another SACP member, Ncumisa Kondlo, from the provincial government.
According to the newspaper, Masualle and Kondlo had been identified as "anti-Mbeki conspirators", members of a group of leftists within the party who were suspected of planning to challenge Mbeki at the ANC's upcoming elective conference.
[15] Indeed, Zuma's favoured candidates lost all the top leadership positions, with Stone Sizani defeating Mcebisi Jonas for the provincial chairmanship.
At the conference, Masualle was elected to a five-year term as a member of the ANC National Executive Committee, with the backing of the Congress of South African Trade Unions (COSATU), the third wing of the Tripartite Alliance.
[27] In the run-up to the April 2009 general election, COSATU and the SACP again lobbied for Masualle to become the ANC's candidate for Premier of the Eastern Cape.
[31][33] However, the vote was apparently swayed by Masualle's decision to select Gugile Nkwinti, a minister and party chairperson in Cacadu, as his running mate.
[34] In the aftermath of the conference, the SACP said that Masualle would likely ask Kiviet to reshuffle the government to ensure that key positions were aligned to the ANC's new leadership.
[32] Indeed, his election apparently "sparked anxiety among ANC moderates about the growing power of SACP members in the ruling party", causing tensions that spilled over to the national level after Billy Masetlha warned in the press that the SACP and COSATU should not attempt to impose their ideology on ANC administrations.
Masualle was appointed to an approximation of the portfolio he had held in Sogoni's government, though the position was now renamed and restructured as MEC for Provincial Planning and Finance.
[4] Masualle's term as SACP treasurer expired in July 2012 and he did not accept nomination to stand for re-election, citing his obligations in the ANC.
[41] After the May 2014 general election, the ANC announced that it would nominate Masualle to succeed Kiviet as Eastern Cape Premier.
[43] In his maiden State of the Province Address in Bhisho in June, Masualle outlined seven strategic priorities for his administration, including "radical socioeconomic transformation", rural development, and food security.
[44] He said that he would pursue rapid industrialisation in the Eastern Cape, particularly through integration with the mining industry and by exploiting South Africa's diversification into nuclear power and shale gas.
[49] After the brawl, only 55% of the delegates remained in the hall, most of them supporters of Mabuyane, and Masualle was not available to formally accept or decline his nomination in the election.
[51] In June 2018, the Johannesburg High Court dismissed an attempt by Masualle's supporters to have the election outcomes declared invalid.
In the same interview, he expressed pride in his administration's economic, infrastructural, and agricultural accomplishments; asked to grade his performance out of 10, he said he would give himself "Anything above seven".
[62] He announced the reshuffle later the same week, with a spokesperson saying that the changes followed from the "new political discourse" in the province and would allow "for a smooth transition" ahead of the May 2019 general election.
[71][55] In addition to appealing to "his former allies on the left", Masualle was expected to boost his campaign by leveraging opposition to Ramaphosa's re-election bid.
[80] On 6 March 2023, Ramaphosa announced a cabinet reshuffle, firing Masualle from the Ministry of Public Enterprises and replacing him with Obed Bapela.