An alliance of minor parties is threatening the Government with the loss of six Lower House seats at the next election, in retaliation to any move to abolish group voting tickets (GVT).

"The potential to exact revenge on the coalition is real," Liberal Democrat Senator David Leyonhjelm told AM.

An excess of 40 minor parties inhabit the political landscape, whose aspirations of parliamentary representation rest on group voting tickets and the preference deals they enable.

Senator Leyonhjelm said ideological differences among minor parties were being cast aside in favour of talks about how to counter the threat to abolish GVT's.

"Running minor party candidates in marginal coalition seats and preferencing the Labor Party is the subject under discussion," he said.

Political consultant Glenn Druery, also known as "The Preference Whisperer", is helping coordinate discussions and says a preliminary hit list of 17 marginal seats has been compiled, including that of Immigration Minister Peter Dutton.

"I think the Coalition may well lose up to six seats," Mr Druery told AM.

The Government has yet to decide whether to move ahead with abolishing GVTs.

Convention dictates the need for bipartisan support for changes to voting procedure, but Labor has not declared a position.

These reforms are poison for the Labor Party: Druery

The Greens would benefit from the extermination of smaller contenders for the balance of power in the Senate, and have long campaigned for the reform.

Greens Senator Lee Rhiannon is pressuring the Government to press ahead with or without Labor's support.

"There are not many weeks left in the autumn session and it really should be introduced in the next week of Parliament," she said.

A deal with the Greens next week would enable the Government to go into a double dissolution election, confident the current Senate crossbench would be largely eliminated with the exception of South Australian independent Senator Nick Xenophon.

Mr Druery is warning Labor such a move would entrench the Greens power on the crossbench.

"These reforms are poison for the Labor Party," he said.

It will put the Labor Party in the position where they may well have to bring the Greens into some sort of formal coalition."