Cory Bernardi’s Australian Conservatives and Pauline Hanson’s One Nation are among the 19 parties who will contest next year's state election, as both sides of politics brace for the possibility of a hung parliament with right-wing parties holding the balance of power.

The deadline closed last week for parties to register to run candidates in the March 2019 election in order to be eligible for electoral funding.

Senator Pauline Hanson during an estimates hearing in federal parliament. Credit:Alex Ellinghausen

Other parties that have registered include Keep Sydney Open, which has campaigned against lock-out laws, the Voluntary Euthanasia Party and the Flux Party, which proposes a direct democracy model, where NSW residents would use an app to vote on every bill in Parliament, with MPs casting their vote based on the result in their electorate.

But it is the return of One Nation, as well as the Australian Conservatives, that is making senior Liberal strategists nervous.