Malcolm Turnbull has suffered a five-point drop in the better prime minister rating in the latest Newspoll, a result which will compound his political woes after his government lost its lower-house majority at the weekend.



In an otherwise largely static poll, which has Labor maintaining an election-winning lead, the gap between Turnbull and the Labor leader, Bill Shorten, as preferred prime minister narrowed substantially, with the margin now two points, with the Liberal leader ahead 36% to Shorten’s 34%. Labor inched forward to improve its lead on the two-party-preferred vote, leading the Coalition by 55% to 45% compared with 54% to 46% in the last poll.

The movement outside the poll’s margin of error on a metric where Turnbull has consistently dominated his opponent will embolden the prime minister’s internal critics, who have been taking regular pot shots as the dual citizenship debacle spirals on multiple fronts.

The Senate is due to sit for a week from Monday in what will be a high-octane few days, which will include intensifying political debate within the Coalition over marriage equality, with the results of the postal survey due on Wednesday.

Conservatives have been positioning in the lead-up to an anticipated yes vote in the same-sex marriage survey, preparing to bring forward a rival bill to increase protections for religious freedom.

Dean Smith, the Liberal senator, who created a marriage equality bill with government moderates which triggered the postal survey process, confirmed at the weekend he would bring his bill forward on Thursday, after the survey result was known.

As well as navigating the marriage debate, the government on Monday will have to resolve on a new Senate president to replace Stephen Parry, who resigned in the citizenship debacle, and later in the week the high court will also hear a challenge to the eligibility of the Liberal Hollie Hughes, who was supposed to replace the former Nationals deputy leader Fiona Nash.

Turnbull is still overseas, attending two international summits, and at the weekend said he intended to see those visits through despite the resignation of the Liberal John Alexander, which has triggered a snap byelection in the Sydney seat of Bennelong and cost the government its lower-house majority.

Alexander will have to clear his citizenship problems by the close of nominations to run in Bennelong, which he holds by a margin of just under 10%. Labor is already fundraising to contest the snap poll, which is expected before Christmas.

Barnaby Joyce is already contesting a byelection in the seat of New England after being ruled ineligible by the high court, in a field with 17 candidates, which will make it hard for him to gain a primary vote over 50%.

With senators due back in Canberra on Monday, the major parties are locked in an escalating standoff over a new disclosure regime to ensure parliamentarians meet the eligibility requirements set out in the constitution.

The government has threatened to send Labor MPs under a cloud to the high court, although it now lacks the numbers in the House of Representatives to follow through on the threat.

Of the 148 remaining members of the House, 74 are from the government, including the Speaker, Tony Smith. Labor has 69 members and there are five crossbenchers.

That means the government cannot win a vote on the floor of the House without the support of at least one crossbencher. This is because winning a vote among the 148 remaining members requires 75 votes.

If Labor and the crossbench voted together, they would have a combined 74 votes, which would be enough to defeat the government, but Turnbull has support for confidence votes and supply from two independents, the Victorian Cathy McGowan, and Rebekha Sharkie from the Nick Xenophon Team – although Sharkie may also end up in the high court to clarify her eligibility.

Turnbull has accused Shorten of running a “protection racket” to prevent a handful of Labor MPs being referred to the high court to test their eligibility.

On Sunday the manager of government business, Christopher Pyne, declared the government would refer Labor MPs to the high court if the ALP refused to do the right thing.

But Labor is making threats in return, declaring it will “go nuclear” and target five government MPs – Julia Banks, Nola Marino, Alex Hawke, Tony Pasin and Ann Sudmalis – if the Coalition refers any Labor MPs to the high court.