THE LAST TIME Virginia made a real effort to increase annual revenue for transportation, state lawmakers heeded the call of then-Gov. Gerald L. Baliles. “The cost is high, there’s no question,” said Mr. Baliles, a Democrat. “But be assured that the cost of failing to act will be far greater.”

In response, the General Assembly enacted a modest bump to the gasoline tax. That was 1986. Since then, the state has stood pat, watching passively as inflation and more fuel-efficient vehicles have shrunk the purchasing power of Virginia’s per-gallon gas tax by more than half.

Today, Virginians do not come close to paying for the roads, rails and bridges they use; at a minimum, the annual shortfall in transportation funding is estimated at $1 billion. The results are predictably dire: A quarter of the state’s bridges are now considered obsolete, and more than a fifth of the state’s road surfaces do not meet federal standards. Even more alarming, maintenance and repair are sponging up dollars so fast that by 2017 not one penny will be left for new construction or even to unlock federal matching grants for new projects.

In the face of this mess, Republicans who control the state’s House of Delegates have delayed, obfuscated, whined and played politics — anything to avoid telling the hard truth that new transportation funding (yes, taxes) is urgently needed. Even a modest measure such as indexing the gas tax for inflation, which would raise a pittance in the first few years, failed in the House this year after Gov. Robert F. McDonnell (R) declined to endorse it.

The governor, who has long recognized the dimensions of the problem but has not acted, now says he is preparing a serious proposal. We’d like to think so. In the meantime, though, one has been offered by a Republican senator, John C. Watkins, who represents a suburban district west of Richmond. It deserves serious consideration.

Mr. Watkins, who has served long enough to have voted for the Baliles transportation plan, would raise $733 million annually by levying a 5 percent surcharge on the wholesale price of fuel and imposing a sales tax on car repairs, car washes and other services related to transportation, which are currently exempt. He estimates that nearly a third of the new gas tax revenue would be paid by non-Virginians passing through the state. He would protect poorer Virginians by cutting income taxes on the state’s lowest brackets.

Measured against the funding deficit, Mr. Watkins’s plan is modest. But Mr. McDonnell, along with House Republican leaders, has treated it as radical. “I don’t support broad-based tax increases in a down economy,” said the governor.

That comment amounts to an abdication of leadership from a chief executive who has repeatedly acknowledged the dimensions of the state’s funding crisis — and repeatedly failed to propose a realistic plan to address it.