The man who helped candidates from micro parties win Senate seats at the last federal election says they are now plotting how to punish the Turnbull Government and the Greens for overhauling voting laws.

Glenn Druery was dubbed the "preference whisperer" in 2013 after helping a number of micro parties win seats in the Senate.

The political strategist said the endangered crossbench senators were furious with what happened in Parliament this week.

"This Green-Liberal Coalition has effectively wiped out the political process to ordinary Australians and many of those ordinary Australians that are in minor parties have said to me that they will be running in marginal [Lower House] seats, preferencing against the Government and preferencing against the Greens," Mr Druery told the ABC.

"Most of them were gearing up to fight the good fight in the Senate; that's now been taken away from them."

The ABC understands many minor micro parties are spending the weekend strategising over what troubles they can cause the Turnbull Government before the Prime Minister calls an election.

Government confident Senate voting laws are constitutional

Family First senator Bob Day has also confirmed he will challenge the Government's Senate voting changes in the High Court next week.

"Senators must be directly chosen by the people. So I'll be asking the High Court a very simple question — is this law valid?" Senator Day said.

The Turnbull Government said it was very confident its changes to Senate voting laws will survive a constitutional challenge.

Special Minister of State Mathias Cormann said in a statement the changes passed by Parliament this week "are consistent with all the relevant requirements in the Constitution".