Scott Morrison has attempted to shake accusations of blatant pork-barrelling as he tries to save a junior minister from political oblivion.
The prime minister is promising to spend billions of dollars in the Victorian seat of Corangamite, which is notionally in Labor hands following a redistribution.
Voters in Liberal MP Sarah Henderson's electorate are being offered the equivalent of $26,500 each in election sweeteners.
"This is a growth part of our country and you've got to invest in the infrastructure and services to support it," Mr Morrison told reporters in Geelong on Wednesday.
"That's why we're investing here, because it needs the investment.
"We make no apology for the fact we're investing in the future of this region, absolutely none."
Asked if the prime minister was trying to buy her seat, Ms Henderson replied: "Absolutely not."
Mr Morrison surveyed yet another housing estate as he sought to sharpen his pitch to first home buyers ahead of the federal election on Saturday.
But a flurry of questions about what will happen if he wins power threatened to bring the message unstuck.
The prime minister is refusing to say who will take on the industrial relations, human services and women's portfolios if the coalition is re-elected.
He argued the national security and economic ministries were his more pressing priority.
"These are the critical portfolios that sit at the central agencies of government."
The prime minister is also not saying who would replace his retiring indigenous affairs minister.
"I'll be making that decision after the election should we be elected," he said.
He also tried to brush questions about legalising same-sex marriage, having opposed it in the 2017 postal vote and then abstaining from the vote in parliament.
"That's not what this election is about," the prime minister said.
"I'm not distracted by this issue at all. I'm 100 per cent focused on the issues Australians are focused on for their future.
"I'm pleased that issue has been settled and put to rest, and I'm very pleased Australians can now move on and plan for their future with confidence."
Mr Morrison is expected to blitz several more marginal seats in Victoria and NSW on Wednesday afternoon.
© AAP 2019