Growing pessimism about the economy threatens to defeat Virginia Gov. L. Douglas Wilder's statewide campaign for a way to speed up financing of transportation projects, according to state and local officials.

If voters approve the two ballot questions Nov. 6, Virginia could finance as much as $1.2 billion in highway and transit construction projects during the next four years, proponents said. Local governments also could raise up to $2 billion statewide, including $360 million in Fairfax County.

The proposals -- one for state government, the other for local governments -- ask voters to make a philosophical switch. Dating back to Gov. Harry F. Byrd's administration in the 1920s, Virginia has had a "pay-as-you-go" approach to financing its roads. Voters are being asked to allow the state to go into debt to pay for some costs through "pledge bonds."

Proponents fear that many Virginians are jittery this fall about the national economy and the financial condition of government at all levels, and may reject ballot proposals that could create additional debt.

"Most people who focus on the merits of pledge bonds will see this as a prudent additional step," said Virginia Transportation Secretary John G. Milliken. "But the voters are being asked to approve this in the context of national uncertainty about the budget. In that context, voters are always cautious, and I fear that caution may be taken out on pledge bonds."

Selling bonds and going into debt is one way state and local governments finance large expenditures for building projects. Typically the bonds are general obligation bonds, which means the sale first must be approved by voters and the debt is repaid from general tax revenue.

A pledge bond is secured by a promise that the issuing state or local government will pay the principal and interest from a specific source of revenue.

For example, if voters give the state permission to issue transportation pledge bonds, the state would repay them with highway user fees such as gasoline taxes and vehicle sales and registration fees.

The second ballot question asks voters to allow city and county governments to issue transportation pledge bonds, which would be financed from revenue other than property taxes. A complex formula would limit the amount a government could borrow.

If the ballot questions are approved, the General Assembly or local governments could start issuing pledge bonds next year and could spend the money without voter approval.

Wilder has made a priority of the pledge bond referendum, which was first proposed by his predecessor, Gerald L. Baliles (D). Baliles was stymied by a state Supreme Court decision declaring the bonds unconstitutional. This year's vote caps a four-year effort to overcome the court's objections.

Hardly exciting to voters, the pledge bond question nevertheless has important implications in a state that officials said will have more than $38 billion in transportation needs over the next 20 years.

Officials said pledge bonds may accelerate road building.

Under the pay-as-you-go approach, the state generally waits until it has accumulated 70 percent of the money before beginning a road project. While fiscally sound, the approach means that road projects frequently are stretched out for several years. Meanwhile, the cost of acquiring land often goes up dramatically, especially in Northern Virginia.

Selling pledge bonds is a lot like buying a house with a mortgage: pledging future income to finance the house right now. This accelerates road building because the state has more money available from the start.

Proponents, who have formed a bipartisan organization that hopes to spend between $150,000 and $200,000 on the campaign, see the ballot questions as a vote to ease traffic congestion.

"That's a great soap advertising campaign, but it falls short of the whole story," said former delegate W. Roy Smith, of Petersburg, one of an informal group of pledge bond opponents that includes former governor Mills Godwin and former senator Harry F. Byrd Jr.

The group does not include anyone from Northern Virginia.

Critics said if the measures pass, pledge bonds could be sold by the state and local governments without voter approval, and the projects receiving money would be left up to the political whims of the General Assembly or local elected officials.

"The gist of this whole thing is to get around the voters," said Del. George Allen (R-Albemarle).

The critics said the state already can sell general obligation bonds for transportation, leaving voters with the final say on projects proposed by state officials.

F.R. (Rick) Bowie, chairman of the Albemarle County Board of Supervisors in Charlottesville, said he is concerned that state officials would pressure local governments to issue transportation pledge bonds so the state wouldn't have to spend its money.

"The state can simply say, 'We won't pay for your roads. If you want them fixed, use your pledge bonds,' " Bowie said.

Pledge bond supporters disagreed, saying the money will be distributed for critical projects identified in a six-year transportation plan.

One supporter, Lt. Gov. Donald S. Beyer Jr., has been trying to raise money from Northern Virginia business leaders to support the pledge bond campaign. The opponents started fund-raising only this week and are "winging it," Smith said.

The next time the measure could be on the ballot would be 1994, but if pledge bonds are defeated this year, lawmakers probably won't submit the idea again soon, some officials said.

"There's a growing anti-bond feeling that's all part of the economic slowdown," said Del. Leslie Byrne (D-Fairfax). "People don't know what the future will bring and don't want to speculate with bond money."