Candidates for state and local offices in Virginia often talk about how they would solve transportation problems. These are some of the reasons.

* Popular Issue In a Washington Post survey taken Sept. 6 to 9, 89 percent of registered voters polled said transportation issues are very important in deciding how they'll vote in the Virginia governor's election Nov. 8.

* The Problem Development in Northern Virginia has overwhelmed the network of roads and rails, and the Washington suburbs are among the most congested regions in the nation.

* History Improving the transportation network has long been a top issue for state government, but proposals for big solutions have not fared well because they involve raising billions of dollars from taxpayers. In 2002, Northern Virginians rejected a proposed transportation tax in a referendum, and proposals to raise the gas tax have not been popular.

* Goals The big projects most often discussed in Northern Virginia are extension of Metrorail to Dulles International Airport, widening of Interstate 66 inside the Capital Beltway, construction of another Potomac River crossing and the addition of lanes on the Beltway and I-95 for use by carpoolers and by drivers without passengers and willing to pay a toll.