Liberal powerbroker Eric Abetz believes his party needs to be more savvy in the face of campaigning by lobby groups like GetUp.

The left-wing advocacy group spent hundreds of thousands of dollars targeting Liberal seats around the country during this year's election campaign.

That included the seats of trumped MPs Andrew Nikolic and Jamie Briggs, as well as Immigration Minister Peter Dutton and the outspoken George Christensen.

The Tasmanian Liberal senator conceded the GetUp campaign was effective.

"We as a Liberal Party clearly need to be a lot more savvy and take on these organisations and expose them for what they are - dishonest, disreputable," he said.

The campaign threw resources at Mr Nikolic's seat of Bass in Tasmania's north.

He held the seat by 4 per cent but a 10.6 per cent swing to Labor on the weekend saw him ousted.

Senator Abetz said it was a brutal attack on the former Australian army Brigadier.

"Trashing the reputation of one of Australia's decorated servicemen, who devoted his life to the service of our country in the military, is just shameful," he said.

GetUp told the ABC it was still finalising the figures for how much it spent on the campaign, but said it had increased its staff from 40 to 70 people, with five devoted to Bass.

It also spent $117,000 on advertising in the northern-Tasmanian seat, with more than 36,000 members funding the public campaign nationwide.

GetUp national director and former Wilderness Society campaigner Paul Oosting said his group had made more than 45,000 phone calls.

"These are conversations with swinging voters on the issues they care about, we've hit the streets and done door-knocking, social media, TV ads," he said.

Of the Liberal seats targeted by GetUp, two were lost and others saw a significant swing towards Opposition parties.

Mr Oosting said his organisation should take some credit.

"The GetUp movement should take a lot of credit and be very proud of the outcome," he said.

"We've stood up to the hard-right bloc and we've seen many of these people face double-digit swings against them," he said.

Soul-searching needed on party's performance: Bernardi

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 7 minutes 27 seconds 7 m Bernardi says voters are now 'suspicious' of major parties

Meanwhile, fellow Liberal senator Cory Bernardi said voters had delivered a message that both major parties were not reflecting their concerns.

Senator Bernardi told 7.30 the Liberal Party had to look at why a significant part of their support base had abandoned them.

Mr Bernardi, one of Malcolm Turnbull's critics, did not call for the Prime Minister to resign, but said there was a general "crisis in confidence in politics" that had to be addressed.

"People don't trust politicians," he said.

"They're suspicious of us and now they're starting to look at minor parties."

Mr Bernardi said both major parties had breathed renewed life into Pauline Hanson's One Nation party by not resonating with public concerns.

"As it currently stands, the Liberal Party's dropped about a million first-preference votes and the Labor Party has dropped about half a million first-preference votes," he said.

"That says to me that the people of Australia are saying, 'Neither of you are doing a good enough job and reflecting our concerns'.

"Those votes have been parked with One Nation.

"In Victoria, they went from having something like 200 votes at the last election to 20,000-odd this one.

"The same in South Australia — it went from 2,000 to 20,000."