Former treasurer Wayne Swan is poised to take over the national presidency of the Labor Party, a position the political veteran will use to highlight economic inequality as his two-decade parliamentary career comes to a close.

With the count of almost 20,000 ballots submitted by rank-and-file Labor members continuing into Sunday night, the Right faction-backed Mr Swan held a commanding lead over Left-aligned Mark Butler, the opposition frontbencher and incumbent president who has campaigned for party democratisation.

Former treasurer Wayne Swan. Credit:AAP

Mr Swan first entered Parliament in 1993 and, as treasurer in the Rudd and Gillard governments, helped steer Australia through the global financial crisis. Since going to the backbench when the Coalition won government in 2013, he has emerged as a strident critic of big business and neoliberal economics.

As of 8.15pm on Sunday, with nearly all of the approximately 10,000 postal ballots counted, Mr Swan had attracted about 48 per cent of the vote to Mr Butler's 36 per cent, according to multiple sources. The paper ballots were counted first, to be joined by almost 9000 online votes.