TORONTO -- There's a lot of support for changing Ontario's election finances rules to limit spending by so-called third parties.

The minority Liberal government is open to a recommendation from Elections Ontario to impose new spending limits on third parties during election campaigns.

Three different union-led groups spent over six million dollars to help the Liberals during the 2011 election.

Attorney General John Gerretsen says the rules may need updating, and Premier Kathleen Wynne says she's willing to consider spending limits for third parties in elections.

It's something Chief Electoral Officer Greg Essensa recommends in his annual report.

The Progressive Conservatives are urging action on the recommendation, and the New Democrats say it should be part of a broader review of the way elections are financed.

The Conservatives have long complained about the Working Families Coalition, which spent $1.6 million in support of the governing party, but were unsuccessful in trying to convince Elections Ontario or the courts that the group is a front for the Liberal party.

Elections Ontario also recommends that voting day be held on weekends or when teachers are off on professional development days so it would be easier to book schools as polling stations.