THEY said it was going to get nasty and that’s what happened today.

Malcolm Turnbull intensified the Liberal offensive in the Sydney seat of Bennelong admitting a Liberal loss in the weekend by-election would cost him his job.

The Prime Minister ramped up attacks on Labor candidate Kristina Keneally for her actions when NSW Premier, and accused Labor senator Sam Dastyari of betraying Australia.

Today Mr Turnbull admitted he was in danger of losing his job in the weekend’s Bennelong by-election. He told reporters a Liberal loss in the Sydney seat would put Labor’s Bill Shorten “very close to being Prime Minister”.

The Coalition barely won the 2016 election with a one-seat advantage in the House of Representatives over Labor and the five members of the crossbench.

“The polls are very tight. It is a tight race,” said Mr Turnbull, visiting the seat with New South Wales Premier Gladys Berejiklian, one of many federal and state Liberal heavyweights recruited to help John Alexander’s campaign.

“And there is a very high cost in voting Labor in Bennelong because if Labor were to win in Bennelong then Bill Shorten would become very close to becoming Prime Minister.”

Labor candidate and former NSW Premier Kristina Keneally is neck-and-neck with Mr Alexander according to opinion polls, and this final week is expected to see both sides intensify campaigns.

Mr Turnbull returned to attacks on Ms Keneally for her ties to jailed former Labor state MPs Eddie Obeid and Ian Macdonald, and for putting them into her Cabinet.

“That’s fact,” the Prime Minister and Premier Berejiklian told reporters, almost in unison.

Mr Turnbull said Labor’s charge that the Government was stirring up anti-Chinese feeling through its pursuit of Labor Senator Sam Dastyari was “desperate and absurd”.

“You could not imagine modern Australia without the one million Australians of Chinese ancestry,” he said.

And he mentioned his granddaughter was of Chinese extraction through her mother.

The Government is demanding Senator Dastyari, who yesterday announced he would leave Parliament next year to stop being a “distraction” for Labor, resign immediately rather than wait until 2018.

However, the timing of Senator Dastyari’s departure depends on when the casual vacancy he would be creating could be filled. That has to be done by a joint sitting of the NSW Parliament expected early next year.

If Mr Turnbull wanted the Labor Senator gone now, he might have today turned to Premier Berejiklian and demanded she recall the NSW Parliament immediately.

“He’s still taking money from the taxpayers of the country he put second,” said Mr Turnbull, referring to the senator’s ties to a Chinese businessman based in Sydney.

“He did not put Australia first. He betrayed Australia by tipping someone off about the activities of our intelligence organisations.”

That was a reference to Senator Dastyari advising the businessman, Huang Xiangmo, to leave his mobile phone inside as they spoke outside his house, to prevent security agencies listening in.

Senator Dastyari has denied passing on information about covert security operations, and said he had no knowledge of them.