RALEIGH - Wake County commissioners have given up on the prospect of asking voters this year to approve a half-cent sales tax to pay for beefed-up bus and rail transit service.

Orange and Durham leaders say they still might consider holding their votes in November.

But it will be May 2012, at the earliest, before Wake voters are asked to consider a tax increase to support transit.

Transportation planners in Wake are running out of time to map detailed bus routes and train plans that would need several levels of approval - by county commissioners and 12 city and town boards - before voters could be asked to pay for them.

"It's not going to be this fall because there is no plan yet," said Tony Gurley, a Wake County commissioner. "That's the big issue."

And, said David Cooke, the Wake County manager, voters might not want to consider a new transit tax this year when state and local governments are preparing to slash spending.

"In the public's mind, it's a tough sell on why - if you're in a position to cut service or lay off employees - to have a conversation about adding a new revenue stream so you can do something new," Cooke said.

Transit advocates across the region had hoped to see all three counties vote together this fall on whether to raise the sales tax to finance a network of better bus schedules and new rail transit lines - either rush-hour commuter trains or frequent light-rail trains, or both.

State law authorizes voters in the three Triangle counties to pay for transit improvements by taxing themselves an additional 5 cents on every $10 sale. The counties can act together or separately if their respective boards of commissioners agree on transit service improvements and on a fiscal plan, and if they vote to hold a referendum.

Planners are mapping routes that would serve residents of each county individually and also connect the region together. Wake's Republican-dominated board has been more circumspect about transit improvements than its counterparts in Durham and Orange. Gurley said he doubted that trains would be acceptable in a Wake County plan, but he hopes to develop some kind of transit plan that he can endorse and put before voters.

"I don't think the economy has recovered sufficiently that the people are going to be willing to vote for a half-cent sales tax increase this fall," Gurley said.

Regional transit officials say they won't push for votes before local leaders are ready.

"We certainly hope we don't lose years, because we think this is a matter of economic competitiveness for the region," said Wib Gulley, general counsel for Triangle Transit, the three-county bus service and planning agency.