OAKLAND — Mayor Ron Dellums made his case Wednesday for a ballot measure to fund 180 new police department employees by hitting property owners with a new parcel tax, saying the tax increase would be a small price to pay for safer streets.

The mayor's appeal came days before Tuesday's election and as some people question why proponents of Measure NN, which would require a two-thirds vote to pass, haven't launched a more vigorous campaign for it.

As for the measure itself, Dellums said even when the tax reaches its highest point, it will only cost single-family homeowners 75 cents a day.

"I don't think you can argue both sides of the fence," he said. "You can't say on the one hand we need public safety, we need more police, but the problem is this is a financial deal-breaker."

Dellums and certain City Council members put Measure NN together after a community group called the Safe Streets Committee proposed increasing police staffing by 272 officers — from 803 to 1,075 — without providing a new revenue stream. The Safe Streets Committee is officially staying neutral in the Measure NN campaign.

Campaign financial statements show proponents of the ballot measure have raised at least $11,000 and have spent $3,330 on Measure NN signs.

The Oakland Metropolitan Chamber of Commerce Independent Expenditure Committee spent $4,449 of its own on a mailer in support of the more-officers measure.

But Greg McConnell, executive director of the Safe Streets Committee, said the group declined to invest resources in Measure NN because the group didn't see much of an effort to get it passed.

"We waited for a signal before we would jump on board and support it," McConnell said. "And we never got it. I think everyone in town wonders why the campaign was so lackluster and so late."

Measure NN would add 105 police officers and 75 police services technicians over a three-year period. It would also mandate the use of a crime-data management system called CompStat, which is used in such cities as New York and Los Angeles.

The new taxes would rise incrementally before leveling off in the third year. Starting in July 2011, owners of single-family homes would pay $276.

Deputy Police Chief Jeff Loman said the new officers would be used to beef up investigations units, including four new homicide detectives.

Other departments that would get a boost would be those addressing youth and services, sexual assaults, robberies, property crimes, identity theft and auto theft.

Loman said the funds would also provide for more truancy officers and other school resources, as well as gang units and traffic enforcement. The technicians would be used to relieve sworn officers of more pedestrian tasks such as injury-free auto collisions and taking "cold reports," when there is no suspect identified in a crime, Loman said.

Critics of Measure NN say the police department has not shown the ability to effectively manage the resources it possesses. They also say officials failed voters in their implementation of police services that were guaranteed under Measure Y, a 2004 ballot measure that funded violence-prevention, fire and police programs.

The city is facing a lawsuit over allegations that it improperly used the Measure Y tax dollars.

Council President Ignacio De La Fuente (Glenview-Fruitvale), who supported Measure Y, but is one of the leading critics of Measure NN, said even with a concerted campaign four years ago, he believes the city has not done its duty to residents.

"We have shown that we are not capable really to keep our promises when you look at Measure Y," he said. "I'm absolutely opposed to (Measure NN). I don't think it's a question of money. And more and more it's become obvious we have a problem with the system here."

Asked about his role in the Measure NN campaign, Dellums said he spoke about the ballot question at a recent town hall meeting he had at Castlemont Community of Small Schools in East Oakland.

But he added he'd been "very much tied up" with Oakland's budgetary woes and had only been able to campaign for the message "only in very selective ways."