One by one, Gov. John N. Dalton summoned Virginia's 34 Republican legislators to his tiny third-floor office in the Capitol last week to hear an unusually impassioned plea.

He was, after all, the governor of the commonwealth and the leader of their party. He had gone out on a political limb to campaign for them last fall. Now he expected their support for the most continuous legislative proposal he has offered in two years in office -- a gasoline tax increase to fund sorely needed highway and Metro construction.

"The governor is knocking some heads," said state Sen. Wiley F. Mitchell Jr. (R-Alexandria). "And I'm not talking about Democratic heads, I'm talking about Republican heads."

As the political strongarming -- a rare event in the gentlemanly atmosphere of the Old Dominion -- suggests, the gasoline tax has emerged as the first real test of John Dalton's leadership. The conservative Republican governor, whom many legislators accuse of being a "caretaker," has chosen to put his political popularity -- and his political future -- on the line.

Dalton clearly has not picked an easy fight. The tax measure is the first statewide proposal that many legislators say Dalton has ever pushed and last week it appeared as popular as a glass of Kepone-contaminated James River water.

Republicans made no secret of their dislike of the proposal, which one GOP senator privately scorned as pouring taxes "into a hole in Northern Virginia." No one -- not even the Northern Virginians whose region stands to benefit greatly from the increased Metro funding -- has pushed to the governor's support.

"The gas tax is his problem, not mine," says state Sen. Adelard L. Brault (D-Fairfax) curtly. "But I can tell you that no Democrats are going to support it if he can't get the backing of his own Republicans."

Senate Majority Leader Hunter B. Andrews (D-Hampton) is blunter, warning that Democrats -- still smarting because Dalton campaigned hard against them last fall -- aren't about to give future GOP opponents any more ammunition.

"We're not getting out front on any gas tax increase that Republicans could use against us in the next election," says Andrews.

Even Republicans, many of whom came away uncommitted from last week's one-on-one sessions with Dalton, are just as wary of being associated with his proposal. The running joke around the statehouse last week was that Republicans would rather switch parties than sponsor any tax bill.

No Republican owes more to Dalton than newly-elected state Sen. Eva F. Scott (R-Amelia). The governor campaigned vigorously for her last fall and aides even helped write some of her speeches. Still, Scott, the Senate's only woman, only laughs nervously when asked if she would be willing to help sponsor Dalton's proposal.

"We're probably going to have to do something" says Scott, who represents a rural Southside Virginia district. "But I have mixed emotions and I'm still not enamored with the idea of having my people, who are poor, pay to subsidize the transit system of a locality whose constituents make three times what mine do."

While support for the tax plan has yet to crystallize, opposition is intense and much of it comes from rural, conservative business interests that have long been a key part of Dalton's power base.

The usually pro-Dalton Richmond Times-Dispatch Thursday published a scathing editorial denouncing use of state taxes for "the solid gold Cadillac of mass transit." The day before the Virginia Agribusiness Council, a coalition of farm and business interests, and the Virginia Gasoline Retailers Association both came out squarely against any gasoline tax increase.

Dalton appeared that same night at the council's lavish legislative banquet to plead for his proposal. He did not once mention Metro, but instead dwelled on the needs of farmers to get their crops to market and pointed out that many rural, secondary roads in the state remain unpaved. "If we don't address the highway revenue problem now," Dalton warned, "we may never get those rural roads paved."

The speech was Dalton's only public comment on his proposal last week. Previously, he had expressed confidence that the legislature would pass some kind of tax increase. But lawmakers from both parties who saw the governor behind closed doors last week said he was clearly upset with the lukewarm and hostile response his proposal had so far received.

Part of the governor's problem is that the revenues from his proposal would be funneled to the state Department of Highways and Transportation, one of the state's most powerful agencies and one that many legislators have grown increasingly suspicious of in recent years.

Critics have accused the department, whose total budget is expected to exceed $950 million next year, of inefficiency, insensitivity to local road needs, and just plain arrogance. Many legislators are concerned the agency could reap a windfall of revenue from Dalton's proposal if gasoline prices continue to rise steeply.

"The highway department does what it wants to do, it always has," say Del. Warren G. Stambaugh (D-Arlington). "Now it's out of money and wants help, but we don't want to give it and still have the department calling all the shots."

To have any hope of passage, Stambaugh and other legislators insist, Dalton and the highway department will have to do a better job of convincing the lawmakers that their localities will benefit. It was only by Thursday -- eight days after Dalton first proposed the tax -- that the department was able that aren't covered in Dalton's proto provide legislators with a list of some highway projects that would be jeopardized without the tax increase.

Northern Virginia, according to the agency's calculations, has more than $96 million of primary roads and bridges planned or under construction, but barely $50 million available in highway funds. The situation is even more critical in other parts of the state.

"That's the governor's ultimate tool -- the recognition on everyone's part that something has to be done or else all localities will suffer," says Dalton press secretary Paul G. Edwards.

A few Democrats see a Machiavellian touch to Dalton's proposal. If the governor wins a tax increase, they say, he can then take credit. If he loses, he can blame next winter's potholes and unimproved roads on the Democrats.

Leaders of the delegation had hoped to seek assembly approval for a separate one percent regional sales tax to cover Metro operation costs which aren't covered in Dalton's proposal. However, it was apparent last week that area legislators are deeply divided about the need now for such a tax and the form it should take.