Slow-growth activists have become an increasingly potent force in Loudoun County supervisors races, and they're pouring money into campaigns as development interests have done for years.

Campaign finance reports filed Friday ahead of the Nov. 2 election show that a Waterford-based political action committee called Voters to Stop Sprawl had raised about $33,000 and had nearly $22,000 on hand at the end of September and that Jeffrey Osborn, a venture capitalist who advocates slow growth, donated $25,000--individually and through his company--to candidates for supervisor.

In a campaign season when developers have been under attack for donating heavily to candidates for supervisor, the anti-sprawl community says it is fighting back by raising money. They say their fund-raising has been more successful than ever because of increased concern among residents about the amount of construction in Loudoun, the nation's third fastest-growing county.

"Everybody realizes that developers raise lots of money and they buy offices with it," said Joe Maio, a spokesman for the anti-sprawl PAC. "We're going to show them that they're not the only people who can do that. We're buying offices for the citizens and not the developers. That's the real big difference."

At least one candidate for supervisor, Eugene A. Delgaudio, a Republican running unopposed in Sterling, said the group is a front for liberals, even though it is supporting some Republicans. "They're a political hit squad for the Democratic National Committee," he said.

After the GOP primary in May, in which Supervisor Scott K. York (Sterling) beat incumbent Dale Polen Myers (At Large) for the nomination as chairman with his slow-growth campaign, several candidates followed his lead and said they would not accept money from developers. Candidates said they feared that developer money would make them appear beholden to builders at a time when residents are clamoring for less development. Some of those candidates have been endorsed by the anti-sprawl group and are receiving assistance from the PAC.

The campaign reports filed last week also showed that York had a decisive fund-raising lead over Myers, who filed to run as an independent after losing the primary. Myers raised $300 in September and listed more than $20,000 in debts.

Myers, who spent more than $100,000 before the primary, said she had shifted strategy and was running a "grass-roots campaign" that does not rely on fund-raising.

York, who received contributions from Osborn and assistance from the anti-sprawl PAC, raised about $4,500 in September, bringing his total on hand to nearly $12,000.

The other candidate for chairman, James G. Kelly (I), reported raising no money in September. He has raised a total of $85.

In the 32nd House District, which includes parts of Loudoun and Fairfax counties, Democratic challenger Kelly Burk raised $17,788 during September, outpacing incumbent Richard H. Black (R), who raised $16,320. But Black had $44,492 on hand, compared with Burk's $17,749.

Although some of the candidates for supervisor pledged not to accept developer money, several have done so.

Republican James E. Clem, a candidate in the Leesburg District and one of those who said they would not take developer money, accepted a $500 contribution in September from Paul Bradshaw, whom Clem's campaign report identified as a general contractor. Clem was out of town and did not return a message left at his office.

In addition, Republican candidate Mark D. Tate, running in the Mercer District, who also said he would not take developer money, accepted a $250 donation from Trow Littleton, a custom home builder who has developed homes and offices in Loudoun. Tate said he would return the donation.

Besides York, Osborn donated to several newcomers--Republican J. Drew Hiatt in the Dulles District, independent William D. Bogard in Sugarland Run, Democrat Charles A. Harris in Broad Run and Democrat Mark R. Herring in Leesburg--and two incumbents, independent James G. Burton (Mercer) and Democrat Eleanore C. Towe (Blue Ridge).

Candidates reporting in-kind contributions from the PAC were York, Hiatt, Bogard, Harris, Herring, Burton, Towe and Democrat Sarah R. "Sally" Kurtz, in the Catoctin District.