RICHMOND -- Virginia faces the prospect of cutting an additional $883 million from its already lean six-year transportation program, state officials said Wednesday.

The grim report delivered to the Commonwealth Transportation Board was based on a prolonged economic downturn that has eroded revenue normally earmarked for roads, rail and transit.

The report underscores the severity of Virginia's transportation funding crisis, which has forced the board to make a series of cuts to the program over the past two years. The board in June reduced the six-year plan by $1.5 billion to $7.4 billion.

"This is about managing expectations," said Secretary of Transportation Pierce Homer. "We have to go through another round."

State officials attributed the projected shortfall to continued weakness in gasoline tax, retail sales tax and vehicle sales tax collections. All three revenue sources are lagging behind budgeted projections.

Transportation officials will present the board with a draft of a revised six-year program next month and the board will hold a public hearing in December before approving another round of cuts.

"There's going to be some time to define priorities," Homer said during Wednesday's meeting. "This is about subtraction, not about addition."

The cuts mostly will affect the Virginia Department of Transportation, which already has laid off workers and reduced services -- including the closure of 19 interstate rest areas -- because of revenue shortfalls. The agency faces a shortfall of $134 million in the current fiscal year, which expires June 30, 2010, and a revenue reduction of $743 million over six years.

The news comes in the waning weeks of a gubernatorial campaign in which transportation has been a key friction point.

Gov. Tim Kaine has failed to persuade the General Assembly to approve new taxes and fees for transportation. The economic slowdown also has affected the state's ability to issue construction bonds authorized under a 2007 bill passed by the General Assembly. The bill called for the state to issue $3 billion in bonds over 10 years and retire the debt with revenue from a tax on insurance premiums. But that tax revenue also has lagged behind projections and the state has yet to issue the first round of bonds.

Republican gubernatorial candidate Bob McDonnell has said he would not raise taxes, but rely instead on a patchwork plan that taps multiple existing and proposed revenue sources and calls for additional borrowing. He also has criticized Democratic candidate Creigh Deeds for leaving the door open for new taxes for transportation.

Deeds has not outlined a specific funding plan, saying that he would appoint a bipartisan commission to tackle the issue next year. Deeds has said he would sign legislation authorizing new taxes for transportation if a bill reaches his desk. He also said he would not divert money from public schools or other essential state services to pay for roads.

Homer on Wednesday also defended transportation officials for their use of nearly $695 million in federal stimulus funds approved earlier this year. Kaine was criticized by a Democratic congressman earlier this month because Virginia ranked dead last among states in spending transportation stimulus money awarded in the American Recovery and Reinvestment Act. Kaine noted that Virginia ranks in the middle of states for how quickly it is obligating funds for projects.

Homer said Virginia has moved more deliberately because it is devoting most of the stimulus money to construction projects with long-term benefits, while other states opt for quick repaving projects that have shorter life spans.

"We in Virginia are saying 'spend the money smarter,' -- and someone in Washington is saying 'spend the money faster,' " Homer said.