He runs at the same time.
The Prime Minister is a normal Member of Parliament (in this case the Member for Bennelong) and can lose his seat like any other MP.
The Prime Minister is not directly elected - rather he is the Leader of the Party that controls the House of Representatives.
It is theoretically possible for the Prime Minister to lose office, by failing to win his own seat, even if his party wins. It's unlikely - but it can happen.
Do you know what seat is his?
Lib/Nat 25
ALP 8
swing to Lib/Nat of 2.75%
Once again, my thanks!
Lib/Nat 33
ALP 12
Ind 2
swing to Lib/Nat of 2.69%
ABC has Lib/Nats - 68
ALP - 42
Other - 4
Channel 9 has Lib/Nat - 47
ALP - 22
Other - 2
76 seats needed for victory