OLYMPIA, Wash. (AP) - 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.

"We think that this Web site runs the risk of making people feel defensive, and that's not what we want," Friedes said. "We want a really open conversation where people can ask questions, express their ideas, and learn."

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.

But while the signatures are publicly available, they aren't published by the state. Murphy, of Seattle, acknowledged that his effort to publicize the information might make some people think twice about signing a petition.

"If this is something they weren't already aware of, then yes, they should consider whether this is something they want to make public," he said.

Murphy also said he was still weighing whether to publish full addresses from signed petitions - one alternative might be to list the signer's city and Zip code, the way registered domestic partners are listed on the state's Web site.

If any phone numbers were listed on the petitions, Murphy said he would not publish those.

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, Stickney said.