PRIME Minister Julia Gillard has accused the Liberal Party of trying to make democracy ''the plaything of cashed-up interest groups'', after the Queensland government opened the door to the abolition of compulsory voting.

Senior Labor Party figures swooped on Queensland's Liberal-National Premier, Campbell Newman, on Thursday after his government released a discussion paper on planned electoral reforms, which included a section on possibly ending nearly a century of mandatory voting.

Outspoken ... Prime Minister Julia Gillard.

Ms Gillard tweeted: ''Fight @theqldpremier's plan to end compulsory voting. Don't let the Liberals make our democracy the plaything of cashed up interest groups.''

Federal Treasurer Wayne Swan also lashed out, comparing the move to the Joh Bjelke-Petersen era, and to the US Tea Party movement.