Senator Zed Seselja admits he was feeling a 'little depressed' about the Coalition's election chances

He had seen the opinion polls published in Saturday's newspapers, which were predicting what had been widely and consistently forecast for three years - a Labor victory.

"I felt like all the polls could not be wrong," Mr Seselja said. "I was bracing for a loss. I thought it would be a close loss, but I thought we would lose."

Less than 36 hours later, Mr Seselja was standing in the backyard of his Macarthur home, Brumbies jumper on, beer in one hand, barbeque tongs in the other, toasting a famous Coalition election victory.

Despite losing all three ACT lower house contests to Labor, and the party's share of the senate vote dipping, those gathered on Sunday afternoon, including volunteers, staffers, family members and failed candidates, were in a celebratory mood.

The Canberra Liberals had largely lost the battle on the home front, but their party had won the war across the nation.

Mr Seselja, who overcame the Unions ACT-led "Dump Zed" campaign to retain his upper house seat, said at various stages during the campaign he felt the party was making ground on Labor.

But that optimism subsided each time an opinion poll predicted a Coalition loss.

"Your gut was telling you that we were making progress, but the evidence that was published was going against that."

It was not until 8pm on election night, as counting showed Labor's nationwide primary vote was tracking lower than anticipated, that Mr Seselja started to sense an election boil over.

One of the architects in the downfall of Malcolm Turnbull, Mr Seselja said Scott Morrison's performance during the campaign, and the final election result, had vindicated the move to change leader.

"It would be hard to point to anyone else who could have done the job that he did to lead us to victory," he said.

On election eve, the Coalition pledge to cut $1.5 billion from the public service over the next four years to fund its election promise, prompting a fierce backlash from Labor, the Greens and unions.

Mr Seselja said he "accepted the challenges around efficiency dividends", but said the public service would continue to "incrementally grow" under the Coalition.

ACT chief minister Andrew Barr on Sunday said the Coalition victory was a "setback" for the second stage of light rail, but the Liberal senator said the project was not contingent on federal funding, and he expected it would "go ahead one way or another".

On his own future, Mr Seselja said he enjoyed supporting Josh Frydenberg and Mathias Cormann as assistant minister for finance, but was reluctant to speculate on what role he might have in Scott Morrison's government.