In the final weeks before the Nov. 3 election, a coalition of Northern Virginia businessmen and developers will air a series of television ads on an issue that goes to the heart of the hotly contested race for Fairfax county board chairman: transportation.

These will not be ordinary political messages: They will mention neither the incumbent, Republican John F. Herrity, nor his opponent, Democratic Supervisor Audrey Moore. And the coalition sponsoring the advertising campaign -- which most likely will cost from about $100,000 to $150,000 -- is the Northern Virginia Transportation Alliance, whose members loudly disavow any partisan leanings.

"We're simply saying we can have a better transportation system if we have an aroused, committed public and public officials who are committed to building a transportation system," said Edward S. DeBolt, a Republican media consultant who is producing the campaign.

Despite the disavowal, several of the major contributors to the transportation alliance campaign are also contributors and fund-raisers for Herrity, prompting some Democrats to voice suspicions about the true intent of the group.

Politics aside, the alliance's education program points to the importance that business leaders attach to unsnarling the county's pervasive traffic jams -- and to establishing themselves in the public's eye as part of the solution to traffic, not part of the problem.

According to a new Washington Post poll, about two-thirds of the registered voters in Fairfax identify traffic and road problems as the No. 1 local issue in the county.

The alliance's television campaign also underscores the transformation of politics in Fairfax County from the neighborly door-knocking affair of 1983 to a costly, media-intensive battle this year, when the total official campaign expenditures for chairman may exceed $750,000.

The transportation alliance is just one of several public relations efforts by Northern Virginia developers and businessmen who say they hope to persuade state and local elected officials to heed the call for better roads. That effort has reached a fever pitch as the contest between Herrity and Moore nears its resolution.

Among the privately sponsored initiatives of recent months:Albert Dwoskin, a prominent Northern Virgnina developer, commissioned a 10-month study, costing more than $100,000, on transportation problems and solutions in the region. The voluminous report was widely circulated among state and local transportation officials and is frequently quoted at public forums on the subject. E.M. Risse, a senior vice president of Hazel/Peterson Cos., a development firm, is organizing a five-part seminar on transportation planning at the Northern Virginia Center of the University of Virginia. Already oversubscribed, the course will address "the fact that there is no comprehensive, long-term regional planning process," according to a course description. The Northern Virginia office of Peat Marwick Mitchell & Co., an accounting firm, completed a study this month showing that Fairfax County has built less than 21 percent of the lanes shown on its 1975 master road plan. The study, which buttresses developers' complaints about the absence of state and local transportation planning, was conducted with the aid of the Northern Virginia Transportation Alliance.

Politicians and transportation planners say they welcome efforts such as the Dwoskin study, which has been widely praised for its breadth and even-handedness.

"It's not that they are saying anything new," said Shiva Pant, the Fairfax County director of transportation, "but it's encouraging that the private sector groups are trying to drive across the same point that we have been, which is that we have limited ability to control growth {and} that people have to start focusing on transportation."

Said Risse, "We're not really trying to influence the debate as much as we are trying to do the work that in normal cases would be expected of the public sector . . . . The bureaucracy at the state and local {levels} aren't providing the transportation system."

But there are also those who question whether some private interests are addressing all sides of the issue.

"I think that businessmen and developers feel they got a bum rap . . . and that there's another story to be told," said Supervisor Thomas M. Davis III (R-Mason). "And I think they're going to tell it in the way that's most advantageous to them. They're advocates, not judges."

Brant Baber, chairman of the Democratic Business Forum, said that "If they were to engage in a major media campaign on the transportation issue prior to the November elections, I would have to question whether they have changed their" assertions of political neutrality.

The transportation alliance was formed last spring as a "business-citizen" group aimed at fostering "long-term planning and implementation of a regional transportation system," according to a brochure.

Democrats charged then that the group did not include ordinary citizens and was set up by developers to help Herrity, who had pledged not to accept the group's money for his campaign. Alliance officials dismiss such claims as unfounded and point to a membership of 500 people as proof of its broad appeal.

Democrats, including state Del. Dorothy McDiarmid (D-Fairfax), have joined the alliance, but the membership still draws heavily from the development and real estate industry.

For example, Hazel/Peterson Cos., one of the largest development firms in Northern Virginia, does not appear anywhere on the list of corporate backers. But a number of employes have joined, from its president, James W. Todd, to several secretaries, to the son and daughter of John T. (Til) Hazel, a company principal and one of the region's preeminent developers.

"They have a right to be in the debate," DeBolt said. "I think it dawned on everybody that the only organized groups who ever spoke at public hearings {on transportation projects} were the negative people."

The alliance has raised between $350,000 and $400,000 in the six months since its inception, according to Michael S. Horwatt, the finance chairman. About 200 people are expected to attend a $2,500-a-plate fund-raiser on Tuesday, although not all are paying guests, Horwatt said.

Horwatt declined to say how much would be spent on the advertising campaign, except that it would be less than $200,000. Horwatt said the campaign also could include radio and newspaper ads.

DeBolt said he had not finished making the television ads and declined to describe their content. According to a source, they will show a map detailing several major roads that have been removed from the master plan.

At the same time, Herrity's campaign is expected to broadcast ads attacking Moore for having opposed several major road proposals in the 1970s. Moore disputes the charge, and contends that Herrity also voted against some of the roads, rattling off a list of her own transportation initiatives.

Earle Williams, president of BDM International Inc. and a major contributor to both the alliance and Herrity, said: "We're not against candidates, we're for roads . . . . There has been a feeling over a number of months that Jack Herrity is more in tune with those of us who feel the roads need to be built, but . . . we will not be against any candidate willing to support the road-building process."