The groundswell began after the dinner plates were cleared. One by one, the Washington representatives of corporate America, gathered at the U.S. Chamber of Commerce headquarters last month, declared their allegiance to Texas Gov. George W. Bush's presidential campaign.

Meeting just across the park from the executive mansion that Bush aims to win back for the GOP 15 months from now, the 16 or so trade association lobbyists who convened that night spoke for a broad and powerful swath of American industry: Oil producers. Supermarket owners. Electric utilities. Forestry and paper manufacturers. Chemical companies.

Their support -- carefully cultivated for more than a year by Bush's Washington allies -- represents a sharp break from the hands-off approach such groups traditionally have taken to presidential nomination battles. Although individual lobbyists routinely back White House candidates, trade association leaders have largely avoided such intimate entanglements with presidential primary politics, believing that it's good business not to take sides when you don't have to.

But the Bush campaign is rewriting that particular Washington canon with an effort led by Thomas R. Kuhn, a Bush classmate at Yale who heads the electric utilities trade group here. His drive to wire the corporate side of Washington has generated significant fund-raising commitments and endorsements from dozens of big business's representatives, according to industry lobbyists.

"It's unusual, even unique, that trade association executives are endorsing this early . . . and that they're overwhelmingly going for one candidate," said Red Cavaney, president of the American Petroleum Institute. Added Tim Hammonds, president of the Food Marketing Institute and a Bush "Pioneer" who has raised more than $100,000, "it is unique in my memory that we've seen such a great amount of enthusiasm so early" among trade group chiefs.

The trade association operation offers a revealing glimpse into how a campaign that aspires to outside-the-Beltway populism has also eagerly exploited every advantage -- financial and political -- Washington has to offer. It also helps explain the outpouring of fund-raising support for Bush from America's corporate boardrooms; for the Bush campaign, Washington serves as a vehicle for recruiting business backers nationwide.

But while Bush's mutual embrace with American business is a fund-raising asset, it also could pose a political risk for the governor. Texas environmental activists, for example, have roundly denounced him for what they say is his cozy relationship with the chemical and oil industries, which the state has allowed to operate aging plants that foul the air and anger residents.

Indeed, the chemical industry, which has worked closely with the governor in Texas and likes his hands-off style of regulation, is one of the most passionately pro-Bush industries, according to several sources familiar with the Bush effort here. Frederick L. Webber, chief executive of the Chemical Manufacturers Association and another Pioneer, has persuaded numerous top chemical executives such as Dow Chemical chief executive William Stavropoulos to help raise funds for Bush, industry officials said.

"This industry has openly said we're going to support Bush and [is] committing to raise a huge sum of money for him," said the head of a major trade association familiar with the chemical group's plans.

Lobbyists for other industries are adopting the same tactics as Webber, generating campaign cash and CEO endorsements from the companies that fund their trade groups -- even as the groups maintain official neutrality. Several said they are embracing Bush, despite knowing little about his positions on their industries' issues, simply because they know that his philosophical leanings are pro-business. But they said Bush also has played off corporate America's deep suspicions of Vice President Gore, warning of his environmental stances and alliances with unions and trial lawyers.

To be sure, Gore can cite support from some prominent business figures, though Bush's stiffest competition for corporate support may come from a Republican rival, Sen. John McCain (Ariz.), who wields power over much of U.S. industry as chairman of the Commerce, Science and Transportation Committee.

But sheer numbers show how lopsided business's pro-Bush sentiment is: In the latest campaign fund-raising reports, Gore listed donations from 264 corporate chairmen and chief executives between April and June, whereas McCain was backed by 121. Bush received donations from 1,542 -- four times as many as the other two combined. In terms of contributions from political action committees (PACs), a traditional gauge of Washington support, Bush received $689,000 this quarter, compared with $77,000 for McCain. Gore does not accept PAC donations.

At the Chamber dinner, the lone Bush holdout expressed the fear of retaliation that traditionally has kept trade group leaders neutral in presidential primaries. Jerald Halversen, president of the Interstate Natural Gas Association of America, which represents pipeline companies, told the other diners he was worried about the remaining 18 months of the Clinton-Gore administration. "We have a lot of issues before the Energy Department, so we can't risk alienating them," Halversen told the gathering, according to one person in attendance.

Few other industry executives share his hesitation. "It's a very, very broad cross section of industries" that is backing Bush, said Kuhn, president of the Edison Electric Institute. "From international trade to the service industries to retail, I think people are very, very excited."

More than a year ago, Kuhn was already preparing the governor's inside-Washington campaign. He called Andrew Card, President George Bush's transportation secretary and at that time president of the American Automobile Manufacturers Association, asking whether Card would be with Bush's son should he launch a presidential campaign.

"I had always placed Kuhn in the trade association camp -- apolitical rather than political," said Card, now General Motors' top Washington lobbyist. "It became clear to me then that George W. did have a network working that I didn't know about."

W. Henson Moore, the deputy White House chief of staff and deputy energy secretary during the Bush administration, also got a call from Kuhn to back the Texas governor. "He was calling people he knew, and the people he knows the best are trade association heads," said Moore, who heads the American Forest & Paper Association and is raising money for the Bush campaign.

The idea, said a Bush Pioneer involved in the trade association effort, was to "drive the industries from the inside." Washington industry groups, the Bush camp reasoned, offer a pipeline to corporate CEOs. And once the CEOs are on board, the fund-raising will follow. After all, "people who represent corporations and trade associations in Washington -- they don't do things unless their clients or bosses tell them to."

Soon, Kuhn and others were flying their recruits to Austin to get the pitch from Bush himself. Other association heads met with him on a trip to Washington earlier this year.

"Bush presents a pro-growth, pro-business message," said the Food Marketing Institute's Hammonds, who decided to become a Pioneer after a trip to Texas. Hammonds expressed confidence that if Bush were elected president, he would please the food industry by dismantling Clinton-era workplace safety regulations that the industry considers heavy-handed.

"Regulators have been an enormous threat to our industry," Hammonds said. "Clinton's taught us the power of driving a regulatory agenda through the agencies," such as the Occupational Safety and Health Administration.

Chemical and oil executives also fear Gore's aggressiveness on environmental regulation while expressing warm feelings for Bush, who has committed himself to light-handed regulation and lower business taxes.

"Our industry is intimately familiar with him, and we've found him to be very approachable," said petroleum institute head Cavaney. "George W. reminds me much more of Ronald Reagan than he does of his father. There are a lot of philosophical similarities, and he also makes people feel respected, even when he disagrees with them."

"We like Bush because of his evenhandedness, his grasp of our issues," said an executive in the chemical industry, which has more plants in Texas than any other state. "We see him as someone we can work with" on the environment. "We want to do things voluntarily," as Bush prefers, he said, "rather than by command and control out of Washington."

But environmental activists say Bush's failure to crack down on polluters is one reason Texas has some of the country's dirtiest air. Texas is one of the biggest industrial polluters among the 50 states, and the federal government has threatened to cut off highway funds to the Dallas area because it has failed to address the problem.

The activists cite Bush's decision to allow the oil and gas industries to operate more than 800 aging plants without complying with clean-air standards. Bush touts a voluntary agreement with companies to work on pollution as a more effective approach than regulation, though opponents note that only 100 plants are participating.

Summing up the environmentalists' complaints, Austin activist Peter Altman said, "The chemical and oil industries like Bush's long record of protecting polluters at the expense of public health."

Staff researcher Madonna Lebling contributed to this report.