Saturday’s by-elections are a free hit for Malcolm Turnbull.

Labor messed up when it believed its dual citizens were safe from the High Court, so they’re at fault for this round of polls.

Plus, history is on the prime minister’s side.

No government has won a by-election from an opposition in 98 years. The expectations are low.

And Turnbull gets a chance to test out his campaign lines ahead of the next general election.

Will tax cuts and power price reductions cut through with voters? How much does he need to scaremonger on immigration? It can all be tried out and measured.

If the Liberals don’t win any of the five seats it’s back to the status quo, and the government can point to 100 years of history to explain away the failure.

There’s more at stake for Bill Shorten.

Overall poll numbers put him in an election-winning position going into the next federal ballot.

But if he loses one or both of Braddon and Longman, questions will be asked.

Anthony Albanese is already positioning himself to take advantage of any chaos that results from potential losses.

If Shorten isn’t winning seats off the government this close to a federal election, the argument will go that maybe he won’t win the big one either.

There is no challenge, but there is definitely a threat.

That said, Shorten also gets to shore up his leadership if he wins and wins big.

The by-elections will also take the pulse of the minor parties, who many voters are still backing.

The Greens have struggled at recent federal elections but they are running in all five electorates.

This will give them a chance to test their vote and potentially shore up some Senate support.

One Nation has pushed hard in Longman, fighting Labor heavily, and Pauline Hanson’s party preferences will likely held decide the seat.

Her recent struggles for party unity could also point to where her vote is headed.

Turnbull either wins on Saturday, or he doesn’t lose.