With about half the Senate vote counted on Sunday,the Coalition appeared on track for about 34 upper house seats – short of the 39 seats it needs to seize outright control.
Labor and the Greens look likely to hold about 36 seats between them,meaning if those two parties voted as a bloc,the Coalition would be forced to negotiate with the crossbench to pass measures such as its $158 billion income tax relief plan.
The previous Parliament's 11-member crossbench looks to have shrunk to six.
The Greens achieved a strong result and are likely toretain all six Senate seats the party contested at this election,despite facing tough fights in three of them.
Jacqui Lambie is poised for a Senate return and warned the Morrison government must treat her"a hell of a lot better"this time around.
Ms Lambie was elected to the Senate in the 2013 election butquit in 2016 after being ensnared in the dual-citizenship saga.