For at least a short period of time, yes. How short - that depends.
Initially, she would be replaced as Prime Minister by the new Leader of her Party - unless she decided to immediately ask the Governor General for an election (it would be reasonable for her to do so), in which case, she would remain caretaker Prime Minister until the election was held in about a month - on current polls, she and her party would be more or less annihilated at this point - and the conservative Liberal Party Leader of the Opposition, Tony Abbott, would become Prime Minister.
Alternatively whoever replaces her as Labor leader and Prime Minister, might ask for an immediate election, in which case, they would be caretaker Prime Minister for a few weeks unless they pull off a miracle recovery - most likely, same end result - Tony Abbott as PM in a few weeks.
Thirdly, if she holds on, or whoever replaces her, might try to hold on until September in the hope of a massive reversal in the polls from their current position.
Fourthly - we have a minority government at the moment, where the Prime Minister is only holding office because of personal deals with some independents. If they chose not to continue their new deal with a new Labor Prime Minister, they could force an election, or even transfer their support to Tony Abbott, who would then become Prime Minister almost immediately. He would most likely immediately ask the Governor General for the election he's likely to win, in which case he would be caretaker PM until the election, and then Prime Minister of a new government.
I doubt that we’d face an election before the budget gets handed out. Whoever is the Labor leader will want to stuff the budget full of pork to try to bribe the voters.
If the government falls then it will be interesting to see how it will impact the budget process. The new government would not have much time to get a grip on the real state of the government’s finances before having to punch out a budget.
Abbott will need to have both guts and brains if he’s going to fix the damage done by 6 years of the Rudd-Gillard/Greens goat rodeo.