With polls predicting Liberal wins in both South Australia and Tasmania on March 15, ACT Chief Minister Katy Gallagher could be the only state or territory leader left flying the flag for Labor government.

The last time Australia was in a similar situation was in the aftermath of Kevin Rudd's 2007 victory, when Brisbane lord mayor Campbell Newman was the most senior conservative MP in power.

With this cheering thought, Prime Minister Tony Abbott took to the stage in Adelaide on Sunday for the South Australian Liberal campaign launch.

''Six months ago, we had a change of government in Canberra,'' he began. ''What we need next weekend is a change of government here in Adelaide.''

The Abbott government was building a ''fair go'' future, he said, before offering a sweeping vision of what life would be like under state Liberal leader Steven Marshall: ''A government that is once more encouraging the people of South Australia to be everything that you can be; to achieve everything that you can achieve, and to slip off the shackles of regulation and pessimism and defeatism, which have held this great state back for far too long.''

Praising Mr Marshall as a man with a plan for South Australia, Mr Abbott said South Australians did not want a premier ''who fights with Canberra''.

''The people of South Australia want a premier that works with Canberra,'' he said.