SAN FRANCISCO , California ( CNN ) -- The California Supreme Court has cleared the way for Californians to vote in November on whether to ban same-sex marriages in the state . A gay couple is married in California in June . Voters could void same-sex marriages in the state in November . The court on Wednesday denied a petition to remove the initiative from the state 's general election ballots . The unanimous decision was handed down without elaboration . Hundreds of marriage licenses have been issued to same-sex couples since mid-June , a month after the court overturned the state 's laws against such unions . However , on June 2 , opponents of same-sex marriage filed for a ballot initiative that would ban such marriages in the state 's constitution . Such a ban would overturn the court 's May ruling . Equality California , a Sacramento-based activist group , filed a petition against the initiative -- Proposition 8 -- arguing that it involves a constitutional revision that ca n't be adopted through a ballot vote . The group also contended that petitions circulated to qualify the proposition for the ballot contained material that misled readers about the measure 's effects . Jennifer Kerns , a spokeswoman for the proposition , called Wednesday 's decision `` a huge victory . '' `` We believe it deals a strong blow to our opponents and sends a strong message that they wo n't be able to keep the ballot initiative away from the people of California , '' she said . Calls Wednesday to Equality California were not immediately returned . If the proposition is approved , it would be the second time same-sex marriages have been voided in California . In February 2004 , San Francisco Mayor Gavin Newsom -- who is considering a run for governor -- challenged the state 's laws against same-sex marriage , ordering city officials to issue marriage licenses to gay and lesbian couples . Those unions were voided by the California Supreme Court , though the justices sidestepped the issue of whether banning same-sex marriage was unconstitutional , allowing legal cases to work their way through the lower courts . Several gay and lesbian couples -- along with the city of San Francisco and gay-rights groups -- sued , saying they were victims of unlawful discrimination . A lower court ruled San Francisco had acted unlawfully in issuing marriage licenses to same-sex couples . However , the state Supreme Court 's ruling in May struck down the state 's ban on same-sex marriage as unconstitutional . That decision made California the nation 's second state , after Massachusetts , to legalize same-sex marriage . Four other states allow civil unions .
California Supreme Court declines to block November vote . State residents to vote on whether to ban same-sex marriages . Activist group had sought to block ballot initiative . Same-sex marriages were legalized in state earlier this year .