Virginia's developers, home builders and real estate agents have more than doubled their campaign contributions from four years ago, a sign that their businesses are flying high and that tensions over growth and sprawl are rising.

Flush with money from a booming housing market, the real estate and construction industries have become the most generous group of campaign donors for Republican gubernatorial candidate Jerry W. Kilgore, Democrat Timothy M. Kaine and independent H. Russell Potts Jr.

By the end of September, real estate developers had given this year's statewide candidates $3.4 million, according to data compiled by the Virginia Public Access Project. By contrast, developers gave $1.4 million to the statewide candidates in the 2001 elections.

Home builders, who gave about $143,000 to statewide candidates in 2001, have quadrupled their political giving during the 2005 campaign, donating more than $573,000 to the candidates for governor, lieutenant governor and attorney general. Real estate agents increased their contributions from nearly $460,000 to about $848,000.

Michael L. Toalson, executive director of the Home Builders Association of Virginia, said the largess from his member companies is evidence that they remain "ever vigilant" against legislation or regulations that would hamper the construction of new homes in such rapidly growing areas as Northern Virginia.

"We take this seriously," Toalson said last week. "This is not a game to us. Every single day, when I come to work, we take the task of this threat very, very seriously. We work hard to keep a favorable housing climate."

The industry has successfully resisted legislators' efforts to grant localities more power to regulate development, an issue that comes up more frequently as the slow-growth movement gains advocates in Washington's outer suburbs. Development interests encourage state spending on services, such as roads and transit, that support new communities.

Most of the money from real estate interests and developers was evenly split between Kaine and Kilgore. Potts, a Republican state senator from Winchester who has struggled to raise money, took in $348,000 of his $1.2 million from the industry, much of it from Northern Virginia developer John T. "Til" Hazel.

Kilgore, the former attorney general, promises to oppose slow-growth measures that builders and developers dislike. He also has proposed to allow regional tax referendums to raise money for roads, something many developers and builders support.

"He is the better candidate to readily address the transportation needs, which are vital to the housing industry," Kilgore spokesman Tim Murtaugh said. "He understands that government should not be in the business of telling people where to live."

Kaine's platform includes a promise to link transportation and land-use planning. This month, Kaine stunned some developers and builders by saying he would push for a law giving local governments the authority to stop construction if nearby roads are not sufficient.

Many developers oppose such rules. Prince William County land-use lawyer John Foote called it a "death knell for economic development in Northern Virginia."

But Peter Schwartz, a commercial real estate investor in Northern Virginia, said many of his peers believe Kaine's proposal will lead to better planning and more livable communities.

"Those of us who are in development for the long run fundamentally know that our assets are going to be less valuable if people can't get to them," he said. "You have got to have in place a set of policies that link land use and transportation. Otherwise you kill the golden goose."

Murtaugh said Kaine's last-minute proposal was a bait-and-switch on the development community, which had invested millions in his candidacy.

"He told them what they wanted to hear for 10 months, then he flips on them, pandering for votes having already cashed the checks," Murtaugh said.

Kaine spokeswoman Delacey Skinner called that charge "absurd." She said Kaine, the lieutenant governor, has always been clear that he wants to ease the state's transportation problems by improving the way local governments and the state plan for houses and roads.

"It is about doing things in a way that is smarter and balances all the interests and different needs of the stakeholders at the table," Skinner said. "Jerry Kilgore . . . keeps using the same old approaches."

Some of the largest contributions this year are coming from developers and home builders in Northern Virginia, but all three candidates have tapped real estate interests from across the state and outside Virginia, according to Virginia Public Access Project data. Kaine and Potts have received six-figure checks from developers in Northern Virginia, while Kilgore's largest real estate donations come from Richmond and Hampton Roads.

Developers have long been a powerful force in Virginia's elections. But they have often been overshadowed by lawyers, retail businesses, finance companies and technology firms.

In 2001, tech companies and their executives gave record amounts to one of their own, Mark R. Warner (D), who was elected governor. But donations from those sources have dropped precipitously this year.

Whoever is elected governor Nov. 8 will almost certainly confront heated debates over development issues during his four years in office. The governor can propose legislation and sign or veto bills regarding the powers of local governments to regulate development.

Developers and slow-growth advocates alike say members of the public -- and the lawmakers who represent them -- are becoming increasingly anxious about the effects of growth, especially on the clogged transportation network.

In Richmond this year, several lawmakers from both parties supported legislation that would have granted local governments the authority to control development or impose fees on builders to cover the impact of new homes.

Dels. Jeffrey M. Frederick and Robert G. Marshall, both Prince William Republicans, introduced measures that would have put limits on development. Del. Joe T. May (R-Loudoun) proposed impact fees to cover the cost of new schools. All three bills were killed in committee.

"The developers and the real estate folks are very powerful in Virginia," said George Mason University Professor Mark J. Rozell, who studies state politics.

Despite success in defeating slow-growth legislation, Toalson said, the recent development battles in Prince William and Loudoun counties have generated new and sophisticated political efforts. That has lighted a fire under some developers this campaign, he said.

"These people have an agenda that is absolutely contrary to the Virginia development community," he said of the groups that often testify against new neighborhoods. "If they had their way, there would never be another house built."

Lisa Guthrie, executive director of the Virginia League of Conservation Voters, leads one of the groups that worry builders and developers. Although her organization has contributed only about $40,000 to statewide candidates, she said, many individual donors look to her group for guidance.

"It's not just us. It's the public as a whole," she said. "We understand the process. In order to get good people elected, you have to make investments."

Guthrie said that a bipartisan commission on growth and sprawl has "heightened the awareness and an appreciation that something has got to be done."

Research database editor Derek Willis contributed to this report.