Opponents of Honolulu's planned $3.7 billion commuter rail system yesterday said they've gathered about half of the signatures needed to put an anti-rail initiative on the November ballot.

The group yesterday said that it has gathered 16,000 signatures since April 21. The group has set a goal of collecting 30,000 to 44,000 signatures by Aug. 4.

Yesterday officials for Stop Rail Now disclosed details of a new plan they hope will generate thousands more signatures. Copies of the petition will be mailed to about 270,000 Honolulu homes via the free MidWeek tabloid.

Those opposed to the project can sign the petition and pay postage to mail it back to Stop Rail Now.

"There's four lines on there so they can get their friends and family to sign in and send it back to us," said Dennis Callan, co-chairman of Stop Rail Now. "We're quite excited to see what kind of responses we get back. This is our effort to give the public the opportunity to participate in a direct way."

Mayor Mufi Hannemann hopes to start construction on the 20-mile commuter rail late next year. The system, which would connect West Kapolei with Ala Moana, is scheduled to open in phases between 2012 and 2018.

Stop Rail Now contends the public has a right to vote on whether the city should proceed with the transit project, which would be the largest public works project in state history. Rail proponents, including Hannemann and pro-rail council members, maintain a vote is not needed as the public has voiced its opinion on the project via elected representatives and public hearings.

Stop Rail Now wants the city to explore traffic-reducing alternatives such as high-occupancy lanes, toll lanes, overpasses and traffic signal optimization.

Studies show the commuter rail line won't prevent traffic along the H-1 Freeway corridor from worsening due in part to population growth in West O'ahu. However, the rail system was found to be the best alternative to reduce future traffic delays, according to the city.

The City Clerk's office says Stop Rail Now will need at least 44,525 signatures of registered voters to qualify for the November ballot.

Whether Stop Rail Now can muster the signatures of enough registered voters remains to be seen. The voter-initiated ordinance process has only been successfully invoked once. That occurred in 1988 and dealt with preventing development of land near Sandy Beach.

Stop Rail Now has one key tool at its disposal that wasn't available in the 1980s — the Internet. The group has solicited donations and made the petition available for downloading via the Internet. Stop Rail Now's MidWeek insert will cost about $20,000. That was funded by donations, Callan said.

Honolulu elections administrator Glen Takahashi said city rules don't appear to prevent such novel techniques.

"When the (city) charter was amended for this process (in the 1980s) it probably wasn't envisioning downloading from the Internet or doing it by mail so the charter is silent in that regard," Takahashi said.