Kelvin Davis will be chosen as Deputy Prime Minister if he wants the role, a political commentator believes.
Prime Minister Jacinda Ardern will appoint her new Cabinet on Monday - the first majority Government since MMP was introduced in New Zealand.
Commentator Mike Williams expects Labour deputy leader Davis to be appointed as Ardern's understudy - but only if he wants the role, which he may not.
Williams, also a former Labour party president, says Davis made some "real gains" in the last Government.
"He's got a lot of pots on the boil," Williams told The AM Show on Monday. "He's made some real gains in the Corrections area - so he may not want the position of Deputy Prime Minister. If he does, it's his for the taking."
Ardern will be forced to appoint a raft of new MPs to replace portfolios previously held by the Greens and ousted NZ First. Former ACT Party staffer and political commentator Trish Sherson, appearing on The AM Show with Williams, expects one of those to be East Coast MP Kiri Allan.
"She was a real performer last time around," Sherson said.
"I think the big one to watch - and this is really Ardern's big one to watch - is Phil Twyford ... I can't see how she can credibly back him."
The Labour party currently lists Twyford at 4, behind incumbent Finance Minister Grant Robertson - also a candidate for the Deputy Prime Minister role - with Ardern and Davis at the top. Originally Housing Minister in the last Government, Twyford oversaw the failed Kiwibuild scheme and he was replaced by Megan Woods.
Twyford also served as Transport Minister. Last month, he said he wanted to "get cracking" with Light Rail after Labour promised to build it from Auckland's central business district to Mt Roskill by 2021 - a project that was suspended in June as Coalition partner NZ First stopped it from progressing.
Williams had positive things to say about Twyford and believes Ardern backs him.
"I'm on the board at KiwiRail and, as Minister of Transport, Phil Twyford's very good - I'd keep him in that position."
Williams said incumbent Health and Education Minister Chris Hipkins, who replaced David Clark following his resignation in July, will likely keep the health portfolio but lose the education portfolio so his workload eases.
"He [Hipkins] will want to stay in education [but] he made such a good fist of health - I suspect that Jacinda will want him in health and put someone else into education."
Labour MPs will hold all ministerial portfolios except for two - with Green Party co-leaders James Shaw and Marama Davidson appointed Climate Change and Family and Sexual Violence Prevention Ministers - both roles outside of Cabinet.
