OLYMPIA — Gay rights supporters plan to publish online the names of people signing petitions for Referendum 71, which seeks a public vote to overturn broader domestic partnerships for same-sex couples.

The effort was announced Monday by a political group called WhoSigned.Org. It is patterned after campaigns in other states where gay rights ballot measures have been proposed.

If R-71 qualifies for the statewide ballot, it would ask voters to either accept or reject the most recent expansion of the state’s domestic partnerships for same-sex couples. Opposite-gender seniors also can register as domestic partners.

The latest expansion, dubbed “everything but marriage,” added domestic partners to all remaining areas of state law where only married couples are mentioned, including the use of sick leave to care for a partner, group insurance policies, and adoption and child custody rights. The partnerships do not affect federal law.

While WhoSigned.Org hopes gay-rights supporters identify people they know among petition signers to discuss the ballot measure, the intent is not to harass anyone, WhoSigned.Org Director Brian Murphy said.

“They’ve got to be relaxed, neighbor-to-neighbor conversations,” Murphy said. “They do not do any good if they are tense and angry.”

Larry Stickney, who is leading the referendum campaign for Protect Marriage in Washington, rejected Murphy’s explanation. The clear intent is to bully petition signers, he said.

“There’s a typical pattern developing around the country, where the homosexual lobby employs hostile, undemocratic intimidation tactics wherever their interests and intents are challenged,” Stickney said.

The petition-listing effort also is not supported by the official campaign trying to keep R-71 off the ballot. Josh Friedes, campaign manager for Washington Families Standing Together, said the group had even asked Murphy not to proceed with his idea, believing the approach too confrontational.

Domestic partnership opponents could have their names and other information published by the Web site only after R-71 petitions are verified by Secretary of State Sam Reed, the state’s top elections official. At that point, the signed petitions are public records, available for anyone.

The referendum campaign needs to collect about 121,000 valid voter signatures by July 25 to make the fall ballot. Supporters plan to start collecting signatures this week.