Three times, Republican gubernatorial candidate Jerry W. Kilgore or his proxies have launched breathless attacks against Democrat Timothy M. Kaine on transportation.

And three times, those attacks have fallen flat, largely because the facts weren't there to back them up.

In each case, the accusations initially had the feel of big news that might have altered the dynamic of the 2005 campaign.

But in the news business, we call these kinds of potential stories "too good to check," because once you scratch the surface, there's less there than meets the eye.

Let's take each one separately.

* The first came in mid-September, in an e-mail with a headline that screamed: "Kaine Transportation Plan: $1.6 Billion Less for Roads."

Wow. If that were true, Kaine could kiss the election goodbye, right? Kilgore aides immediately set up two conference calls with reporters and a series of Republican delegates and senators to blast Kaine for his proposal.

"The hit to road-building and construction and maintenance cannot be overstated," said Sen. James K. "Jay" O'Brien Jr. (R-Fairfax).

In fact, it could be. And was.

Kilgore was alleging that during the Sept. 13 debate in Fairfax County, Kaine had said he wanted to change the formula by which the state apportions money among roads, bridges and mass transit. In fact, what Kaine said was that he wanted to adjust a state "subsidy" that for years has favored roads slightly over transit.

The lawmakers backpedaled, but only reluctantly, when they realized they had leaped too quickly.

"If there is confusion, that is also his fault," O'Brien said.

* The second attack came a few days later, when Del. Timothy D. Hugo (R-Fairfax) released an e-mail with the subject line: "Warner/Kaine Transportation Cuts."

It was not as over the top but still was potentially devastating to Kaine, who must win big in Northern Virginia -- with all its traffic congestion -- if he hopes to be governor.

Hugo's premise was that Gov. Mark R. Warner (D) and Kaine had a "plan" to stop transferring about $145 million a year into the state's transportation fund from its general fund. His evidence: a presentation by the state's budget director that showed the money being taken out of the "base budget" used by bean counters to prepare the next spending plan.

Backed by House Speaker William J. Howell (R-Stafford), Hugo expressed outrage.

"These new Warner/Kaine budget cuts, if left uncorrected, will result in a reduction of over $1 billion in the six-year transportation plan," Hugo wrote.

But Warner aides, including the budget director, asserted that no decision had been made. The "base budget" presented to the House Appropriations Committee had been a working document, they said, and Warner had made no decision yet about the transportation funds. He presents his budget in mid-December.

In the end, it was a "he said, she said" exchange, and Hugo had no real proof that Warner and Kaine wanted to yank the road-building cash.

* The third transportation attack came last week, when Kilgore himself accused Warner's Department of Transportation -- and, by association, Kaine -- of delaying much-needed road projects by failing to request federal money in a timely fashion.

"While motorists sit in traffic, the money that can remedy this situation sits in Washington," Kilgore said. "That is not acceptable."

Warner and his aides went ballistic, calling the charge completely false. The delays were purely bookkeeping issues, and no projects were ever held up, they insisted.

Behind the scenes, both sides urged reporters to call the Federal Highway Administration for confirmation. Warner spokesman Kevin Hall said the agency would confirm that no projects had been delayed. Kilgore spokesman Tim Murtaugh said the office in Washington would confirm that projects had been delayed.

In the end, the Federal Highway Administration issued a comment that said nothing. (The regional office in Richmond has worked closely with the Warner transportation department, while at the highway agency's national office, Charles D. "Chip" Nottingham is a senior official. Nottingham was the secretary of transportation for Republican Gov. James S. Gilmore III, Warner's predecessor.)

Two days later, the nonpartisan American Association of State Highway and Transportation Officials released a letter backing Warner's version of events. On the radio, Warner blasted the Kilgore attack as "a case of some very sloppy staff work and a blunder by a campaign or an attempt to mislead."

At the very least, all three were attempts to see whether something negative would stick.

For the most part, it did not.