Senator Nick Xenophon is the South Australian “vote magnet”. He is making both the Coalition and Labor nervous as he spreads his brand at this election. His probable success promises not just more Senate seats for the nascent party but a powerful role in the new Senate for its leader.

Xenophon tells Michelle Grattan he believes that while governments have a mandate to introduce legislation, the Senate has a mandate to scrutinise.

“I say that in the context that there are many hundreds of thousands of Australians that vote differently between the lower house and the upper house because under our Constitution, under our system of government, the Senate is there to represent the states.

“It’s also there under its proportional representation system to be a bulwark against excesses of executive power,” he says.