Voting for Labor's national presidency will close on Friday as federal MPs Wayne Swan and Mark Butler battle it out.
The former federal treasurer Mr Swan is considered the favourite as Mr Butler's vote is expected to be diminished by two other left-wing candidates.
Mr Butler, the incumbent president, is fighting on a reform agenda, but his spot is under threat thanks to the CFMMEU's decision to run a candidate and split the Left vote.
He won the presidency in 2015 but has largely not been able to achieve the reforms he called for.
Mr Swan is retiring at the next federal election, while Mr Butler is looking for a new seat after his was slated for abolition in a recent boundary redraw.
The ballot closes on Friday, with the party's national returning officer due to announce the results once votes are counted.
The party's national conference will be held in December.
Australian Associated Press
