Labor frontbencher Sam Dastyari has predicted Malcolm Turnbull will be gone by the half-way mark of his three-year parliamentary term.

It’s no coincidence, Mr Dastyari suggests, that former Liberal leader Tony Abbott is out and about running his own campaign.

“You don’t suddenly start going around the country giving speeches on the economy as a backbencher from Waringah,” Senator Dastyari told Sky News on Sunday.

Senator Dastyari predicted Mr Turnbull would not last any more than 18 months as Prime Minister.

“We sat here and we had the exact same conversations about Kevin Rudd and we were saying ‘It can’t happen, it can’t happen’, and it happened. Of course Tony Abbott thinks it can happen,” he said.

“This isn’t not premeditated; he’s not walking around giving these speeches, building up these issues, reminding people he’s around, talking about his legacy, for any reason other than this is a guy who’s having another tilt at the leadership.”

His comments follow Labor’s landslide victory in the Northern Territory, and on the eve of a new session of parliament.

Sam Dastyari says Abbott is eying the top job. Photo: Getty

Meanwhile, Mr Turnbull believes the Senate crossbench would have been even larger without a double dissolution election, with 12 senators rather than the 11 it ended up with.

But Mr Dastyari says it is still a tough upper house.

“The goverment went to a double dissolution with the aim and goal of having a better Senate … this is not a better Senate,” he told Sky News, noting a block of four One Nation senators, a three-strong Nick Xenophon team, and a variety of independent senators.

WITH AAP