Our news partner KIMA Action News is reporting that R-74 supporters turned in petitions with enough valid signatures to put the measure on the November ballot.

Preserve Marriage Washington submitted the signatures on Wednesday, just a day before the state was to begin allowing same-sex marriages.

The law, passed by the Legislature and signed by Governor  Gregoire earlier this year, would make Washington the seventh state to have legal same-sex marriages. National groups have already promised time and money to fight the law.

Washington state has had domestic partnership laws since 2007, and in 2009, passed an "everything but marriage" expansion of that law, which was  upheld by voters after a referendum challenge.

Same-sex marriage is legal in six states and the District of Columbia. Maryland passed a same-sex marriage law, but is poised to have a public vote on the matter this fall.