Kevin Rudd's price for being co-opted to head the ALP at the 11th hour was the introduction of tough new rules that make it almost impossible for the party to change parliamentary leaders between elections.

Bill Shorten, rather ironically given the roles he played in dumping first Rudd and then Gillard, has been the unexpected beneficiary of those reforms.

While Mr Turnbull's record on losing opinion polls is now at least as bad as Tony Abbott's was when he was dumped, Mr Turnbull has one redeeming feature.

He has consistently trounced Bill Shorten, Kevin Rudd and Julia Gillard in the preferred Prime Minister stakes.

That wasn't the case with Mr Abbott who remains unpopular within his own party, on the nose with the electorate and palpably unelectable as a recycled leader.

Mr Shorten, despite the multiple layers of protection he receives from the ALP's rules and regulations, is in a less fortunate position.

Labor is faring far worse than anybody, especially its own supporters, would have expected in the lead-up to the Super Saturday by-elections this weekend. It is now at risk of losing either Longman in Queensland or Braddon in Tasmania, or even possibly both, to the Liberals.

Weekend polling indicated both seats were balanced on a knife edge. 49 per cent of the Longman voters contacted supported Labor. 51 per cent supported the Liberals.

When asked how they would vote if Anthony Albanese, the man beaten by Mr Shorten under the new rules for the ALP leadership, was opposition leader, 52.2 per cent said they would vote Labor. 47.8 per cent said they would vote Liberal.

The outcome for Braddon was very similar with 50 per cent supporting Labor and 50 per cent supporting the Liberals (two party preferred). The probable ALP vote rose to 53 per cent under the Albanese scenario.

It is remarkable the ALP is performing so poorly midway through a year which began with the Coalition facing a major crisis thanks to the Barnaby Joyce.

One would have thought the opposition would have romped home in a series of, admittedly self-inflicted, by-elections.

If, under Mr  Turnbull's leadership, the Liberals do snatch one of the Labor-held seats it will be the first time in almost a century a by-election has gone to the Government.

While that would be a major feather in the PM's cap it would be a very dark outcome for Mr Shorten.

Labor has not been helped by the controversy that has flared up over western Sydney MP, Emma Husar, who is embroiled in allegations she misused the Comcar service, verbally abused staff members and used tax payer funded staff members to walk her dog, provide childcare and even wash the dishes.

That issue, kept quiet for months under the guise of a party investigation, became public at the worst possible time for the ALP. It also adds to the questions about governance within the ALP raised by the party's failure to comply with s.44.

If the Husar affair has a further negative effect on the by-election results this may well be the beginning of the end for Mr Shorten.