The campaign echoes Brash's infamous "one law for all" speech at Orewa in 2004 and the Iwi/Kiwi billboards used when he was National Party leader.
National Party campaign chairman Steven Joyce said today that times had changed, and he did not see the new campaign as a threat.
"The difficulty in what he's focusing on is that most New Zealanders realise we take a very balanced approach to these issues.
"On that basis, I don't have a particular concern about it.
"We see these sorts of groups every election and Don's views about this stuff have been known for more than a decade."
Labour leader Andrew Little said the campaign was ignorant of the first 100 years of New Zealand's history, when Maori faced land confiscations, unlawful detention, racism and discrimination.
"Most New Zealanders are now sufficiently literate about our history where this stuff looks like a bunch of old fuddy-duddies who are pushing a barrow that has long had the wheels fall off it."
Act Party leader David Seymour said there were aspects of Hobson's Pledge that he agreed with. He opposed the creation of specific Maori positions within local government and Resource Management Act proposals which give iwi a new role in consenting decisions.
But Act's position on Maori issues were changing, he said.
"If you look at where Act's going today ... partnership schools have been overwhelmingly endorsed by Maori.
"If it came down a choice between scrapping Maori seats and reforming education so that people have real choice ... I don't need to tell you which is Act's priorities these days."
'We are now one people'
The campaign is named after New Zealand's first Governor General William Hobson, in particular his statement that "we are now one people" after signing the Treaty of Waitangi in 1840.
On its website, the campaigners say they will back any parties which oppose all laws, regulations and policies "that provide for any entitlement based on ancestry or ethnicity".
Brash said some of group wanted to form a new political party, but he believed a one-issue party was doomed to fail.
Instead, the group will run an advertising campaign in community newspapers over the next two weeks, and distribute donations to candidates or parties.
Brash said that could put him in the unusual position of donating money to New Zealand First leader Winston Peters, who was once a sworn enemy.
"As it stands at the moment, the only political party which is making an issue of this is New Zealand First," he said.
"Someone with my particular background is not wildly enthusiastic about that."
Peters has been asked for comment.
The National Party once had "very good credentials in this area", Brash said, and he supported the Government's acceleration of the Treaty settlement process.
However, National had no plan to scrap Maori electorates, despite the relatively high proportion of Maori MPs in Parliament, he said.
Hobson's Pledge was formed in response to several recent proposals or rule changes within local government and central government.
In particular, the group was concerned about proposed changes to the Resource Management Act (RMA), which it believes will increase iwi involvement in planning decisions.
The Government rejects this, saying that the RMA changes simply streamline the consent process by allowing iwi to be involved at an earlier stage, reducing the likelihood of disagreement and litigation.
Brash also criticised a recent proposal to increase Maori representation on the New Plymouth District Council and the establishment of Auckland Council's Independent Maori Statutory Board.
"It seems to me that we are moving down a track that is entirely inconsistent with what the Treaty of Waitangi involved and with what Governor Hobson said as each chief signed the Treaty."
