Labour leader Ed Miliband is confident of winning the approval of his MPs and peers for an internal party reform as he seeks to bolster his authority.
Aides said they expected a "significant level of disagreement" over a move to dispense with elected shadow cabinets in favour of handing the leader a free rein.
They believe however that a secret ballot among the Parliamentary Labour Party (PLP) on Tuesday will back the change - paving the way for it to be put to activists at the annual conference.
Few opposing voices were said to have been raised when the PLP met on Monday night to discuss the change - which it rejected by a margin of two to one in a vote only last year. Though the vote has no force, it will be hugely significant to the fate of the reform.
Mr Miliband has faced criticism from the left of the party after speaking out against strikes by public sector workers at a time of ongoing pension talks between ministers and unions.
At the weekend, former attorney general Lord Goldsmith accused Mr Miliband of damaging Labour's prospects by excluding major talents from the Blairite wing of the party from his shadow cabinet.
The peer - a close ally of Tony Blair during his time in power - said he had failed to connect with the public, to prove he could get Labour back to power or to show what he stood for.
James Purnell, who stood down as an MP at the 2010 election, was "potentially a very important figure in the Labour Party" who was not being allowed to contribute, he suggested.
Last week, Mr Miliband urged MPs and peers to accept the change to the way shadow cabinets are chosen as part of efforts to show the party was no longer "inward looking". Forcing the party leader to choose his shadow team from a pool elected by their peers every two years pits colleagues against one other and skewed decision-making, Mr Miliband believes.
Instead he wants the "everyday accountability" of senior figures appearing before a backbench committee and a non-voting place for the chair of the PLP in the shadow cabinet.