Hanson puts Labor last, throws Morrison lifeline

Pauline Hanson has thrown Scott Morrison a political lifeline by putting Labor last on One Nation how-to-vote cards in four critical seats.

Meanwhile, the coalition government has described Clive Palmer as the "least worst" option, after striking a political deal with the billionaire in South Australia.

Senator Hanson has significantly lifted the Liberals' chances of retaining four seats, including Home Affairs Minister Peter Dutton's Queensland seat of Dickson.

"Peter Dutton has been one of the toughest ministers on border security and has worked constructively behind the scenes with my office on matters of national security," she told the Courier-Mail this morning.

One Nation will also put Labor last in Attorney-General Christian Porter's Perth seat of Pearce, former soldier Andrew Hastie's WA electorate of Canning, and Luke Howard's north Brisbane seat of Petrie.

Senator Hanson said debate around the Adani coal mine had influenced her thinking.

"Bill Shorten and Labor have made it very clear that the majority of their elected members want to shut down of our coal industry in Queensland and NSW which will leave tens of thousands of workers out of jobs," she said.

"I won't support him on that decision."

In 2016, One Nation placed sitting MPs last, contributing to the LNP losing the Queensland seats of Herbert and Longman.

The Liberals are preferencing One Nation candidates behind Labor on their how-to-vote at the election, after the National Rifle Association lobbying scandal.

But the Coalition will preference Mr Palmer's United Australia Party second on its Senate how-to-vote cards in South Australia.

"Sometimes it feels like you are allocating to the least worst out of a whole bad bunch of alternatives," Liberal Senator Simon Birmingham told the Adelaide Advertiser.

"We have problems with the policies and the positions that every other political party holds - ultimately we don't endorse any of the rest of them."