(Olympia, Wash.) A referendum on an expansion of Washington’s domestic partnership law for gay couples has qualified for the November ballot, election officials said Monday.

The “everything but marriage” measure broadens recognition of domestic partnerships by granting gay and lesbian couples all the remaining state-provided benefits presently extended only to married heterosexual couples.

After a month of counting petition signatures, the secretary of state’s office said that Referendum 71 had 121,486 valid signatures – nearly a thousand more than needed to advance to the general election.

But supporters of the expansion of the law asked a King County Superior Court judge on Monday to at least temporarily block the referendum from the ballot, arguing that election officials have accepted thousands of invalid petition signatures.

The new law was supposed to take effect on July 26. But the referendum campaign put it on hold, and the law can now only take effect if approved by state voters Nov. 3.

It would expand the domestic partnership law passed in 2007 that granted gay couples hospital visitation rights, the ability to authorize autopsies and organ donations, and inheritance rights when there is no will.

Lawmakers expanded that law again in 2008 to give gay domestic partners standing under laws covering probate and trusts, community property and guardianship.

The new benefits under the current measure for gay couples range from adoption and child support rights to public employment benefits – although any benefits that cost the state money, such as pensions, are delayed until 2014 because of the state’s recession-fueled budget problems.

If the referendum leads to a rejection of the law’s expansion, legislation approved in 2007 and 2008 would be retained, but it would roll back the additional rights granted in the “everything but marriage” bill.

As of this week, more than 5,800 domestic partnership registrations had been filed in Washington since the first law took effect in July 2007.