The newly launched Liberals for Yes campaign group is fronted by two prominent members of the party in the ACT.
The "national convenor" of the movement to promote a "yes" vote in the referendum on a Voice is Kate Carnell who was the ACT's chief minister from 1995 to 2000. The current Liberal leader in Canberra, Elizabeth Lee, is in the lobby group's leadership core.
The Liberals' campaign for a body to represent the views of Indigenous people to parliament runs counter to the policy of the national party.
But the convenor of the "yes" group denied this meant a fundamental split.
"The Liberal party is a broad church," Kate Carnell said. "We recognise and respect that there are a range of views both within the party and the wider community, but we are united in our belief that this referendum can be a moment that brings Australians together.
"There are people who are conservatives and people who aren't conservatives. That's what makes up the Liberal Party. Ever since the Menzies era, the Liberal Party has always been seen as a broad church with a really, definite focus on middle Australia."
She denied that a broad church was a divided church.
But Peter Dutton, the federal Liberal leader, said the Indigenous Voice to Parliament would "re-racialise our nation".
The proposal, Mr Dutton said, would "permanently divide us by race.
"Changing our constitution to enshrine a Voice will take our country backwards, not forwards."
But the pro-Voice Liberals fear that opposition to the measure would sit badly with many voters who tend to vote Liberal but who aren't party members or committed party supporters.
Ms Carrell said that the group's formation was prompted partly by grassroots opinion.
"As Liberals we have been motivated to support the 'yes' campaign based on strong community feedback from people across the country who want to see practical and positive change on Indigenous issues," she said.
"We aim to help empower all Australians, and especially Liberals, to be confident and active in supporting the broader 'yes' movement, which is fundamentally about people and not politics."
The new group is not a formal part of the Liberal party. Its members emphasise that they speak as individuals and not on behalf of other organisations.
The group plans to hold campaigning events throughout the country, often at a local level.
"Constitutional recognition of Indigenous Australians has been championed by Liberals," Ms Carnell said. "After a decade of consultation, we approach a referendum where the Australian people will be asked if recognition should be in the form requested by Aboriginal and Torres Strait Islander people. We say the answer is 'yes'."
