Scott Morrison’s approval has taken a sizeable hit in a Newspoll showing Labor maintaining its 52-48% two-party lead.

As Morrison prepares to unveil his cabinet reshuffle the poll, published in Monday’s Australian, found his satisfaction rating fell from 62% to 55% in two weeks.

The fortnight was dominated by shocking revelations of lewd behaviour among staffers on the Coalition side, a botched attempted “reset” on gender issues when Morrison lashed out at a news conference, and a scandal around a Liberal backbencher.

In the poll, taken March 24-27, Morrison’s dissatisfaction rating jumped from 34% to 40%.

The “better PM” gap also narrowed – Morrison now leads Anthony Albanese 52% (down 4 points) to 32% (up 2 points). This the narrowest margin since March last year. In February Morrison had a 35-point margin.

The Coalition’s primary vote rose a point to 40% while Labor’s fell a point to 38%.

The Australian reports that it is the first time in more than a year that Morrison’s approval ratings haven’t been in the 60s. His net satisfaction is plus 15.

Albanese’s satisfaction increased one point. He has a net satisfaction of plus 2.

The reshuffle is set to move Christian Porter out of the attorney-general’s portfolio and Linda Reynolds out of defence, but keep both in cabinet.

The government is now confronting a major row over Queensland Liberal MP Andrew Laming who trolled two local women on Facebook and took an inappropriate photo of another woman.

Laming announced at the weekend he would not seek to run at the next election but he remains in the Liberal National Party. He is now on leave but has indicated he aims to be back for the budget session, after he has had counselling on “empathy and appropriate communications”.

Albanese said Laming was not a fit and proper person to be in parliament and should go. He said there were various measures available to the Labor Party to take against him when parliament resumed.

Morrison will be anxious to see a woman preselected for Laming’s seat of Bowman.

As the government’s crisis continues Liberal women are increasingly speaking out, with Victorian federal backbenchers Sarah Henderson and Katie Allen suggesting on the ABC’s Insiders that parliamentarians should be subject to drug and alcohol testing.