The Labor minority government effectively lost one Labor vote on Sunday when embattled backbencher Craig Thomson quit the party to sit on the crossbench as an independent.
Mr Thomson has been the focus of claims of misuse of Health Services Union (HSU) funds during his time as its national secretary.
The government has also been forced to replace Peter Slipper with Labor deputy speaker Anna Burke in the Speaker's chair because of separate allegations of taxi voucher misuse and a sexual harassment civil lawsuit.
Responding to questions about getting the budget passed, Ms Gillard pointed to the government's track record in getting legislation through parliament.
"Last year we passed the budget bills in record time," she told reporters in Canberra on Sunday.
Mr Thomson later on Sunday said he would support the government in no-confidence motions and supply bills and stressed he was a Labor man with Labor values.
Ms Gillard said the government would be handing down a budget in surplus that was "unambiguously in the interests of our nation today."
Ms Gillard said her recent overseas trip made her reflect on the turmoil facing European economies which have high unemployment and huge debt levels.
"Here we are in Australia, due to the careful management of the government, with a stronger economy, strong fundamentals and low unemployment," she said.
"(The surplus) will give us a buffer for the future."
Treasurer Wayne Swan warned that global uncertainty was hitting government revenues.
"I can tell you it will hit budget revenues to the tune of $5 billion in 2012-13 and $5 billion 2013-14 and that will mean over five years there's been something like $150 billion lost to Commonwealth revenues," Mr Swan told Network Ten on Sunday.
"We have to do what is right and bringing the budget back to surplus in these difficult conditions, with the revenue write-downs is absolutely the right thing by the Australian economy."
Earlier on Sunday, key crossbencher Andrew Wilkie promised not to block supply to the Gillard government.
Mr Wilkie said he would support the government's two appropriation bills that gave the government the authority to spend money in the next financial year.
"A government is entitled to have control of the treasury bench and to be able to pay public servants to be able to pay Centrelink benefits and so on," he told ABC TV.
Mr Wilkie said he would make no promises to back the government's "enabling legislation" - dozens of bills that underpin the budget.
"I'll approach each one of them on their merits and vote accordingly," he said.
Fellow independent Rob Oakeshott said he wanted federal cash for the Pacific Highway on the NSW north coast in the next budget to match the NSW's government's commitment.
He is also looking for progress on comprehensive tax reform.
"Hopefully it hasn't dropped off the agenda and we do get some movement," he said.
