Kevin Rudd is unlikely to take any further part in Labor's bid to retain his Brisbane-based seat of Griffith.
The former prime minister's famous personal magnetism with voters, particularly in Queensland, appears to have dimmed since he led Labor out of office and quit Parliament.
Fairfax Media understands Mr Rudd's popularity is no longer a net positive for the ALP as both sides poll the mood among the people he affectionately refers to as the ''good burghers of Griffith''.
It was said that during his political career Mr Rudd started 5 per cent ahead of any LNP opponent due to his personal following, but the backlash at forcing voters to the polls twice in five months has taken a toll.
Since quitting, he has been on an intensive round of international meetings and speaking engagements, and is again overseas, but he has made himself available if called upon to assist Labor candidate Terri Butler.
His spokeswoman said: ''Mr Rudd has campaigned with Terri a couple of times over the last week or so. He will do so again during the remainder of the campaign as required.''
Mr Rudd is due to fly back to Australia later this week. On the say of the byelection, Mr Rudd is scheduled to give a speech in Sydney for the coming anniversary of his national apology to the stolen generations.
Prime Minister Tony Abbott has committed to campaign with LNP candidate Bill Glasson.
Ms Butler is a clear favourite with bookmakers.
She has history on her side. The only time a government has gained a seat from an opposition was at the 1920 Kalgoorlie by-election.
But Labor strategists believe the closest parallel is the 1992 Wills byelection prompted by the resignation of Bob Hawke. Labor failed to retain the seat, won by independent candidate Phil Cleary.
Labor will seek to capitalise on uncertainty about the government's intentions, particularly the budget pain currently being mapped out by Mr Abbott's Commission of Audit.
A spokeswoman from Ms Butler's campaign said she had received strong, continuing support from Mr Rudd, as well as Opposition Leader Bill Shorten, who campaigned in Griffith for four straight days last week and held a shadow cabinet meeting in the electorate.