AUGUSTA — A Brunswick law firm that specializes in labor and Workers’ Compensation cases was the biggest single campaign contributor to either Gov. John R. McKernan or Rep. Joseph E. Brennan, according to reports filed this week.

With 15 lawyers and nine of the lawyers’ spouses each giving $1,000 to the Brennan campaign, the firm of McTeague, Higbee, Libner gave the Democratic challenger for governor a total of $24,000.

Labor unions gave the Brennan campaign at least $16,500 and eight cable-television companies gave Brennan a total of $11,000.

For McKernan, the Republican governor seeking re-election, Maine fuel-oil companies and their executives gave at least $16,000 while real-estate investors and developers gave at least $9,000.

Nearly all of the $272,000 raised by McKernan so far has been from within Maine.

Brennan has gathered more out-of-state support than McKernan so far and exceeds McKernan with $353,000 in campaign funds raised.

Each candidate is expected to spend more than $1 million before their showdown in the November election.

Lawyers were the most numerous among major contributors to both candidates for governor.

But the $24,000 donated by McTeague, Higbee easily outdistanced all other law firms.

“I’ve known Joe Brennan for 30 years. We’re all Democrats here,” said attorney Patrick McTeague, whose firm has 16 lawyers. “We represent a great number of unions and workers in Maine. It’s the nature of the work we do. The theme of our office is very much along progressive Democratic lines.”

McTeague said lawyers in his firm felt there was “a vast difference” between McKernan and Brennan from the workers’ point of view.

Of McKernan, McTeague said, “Every time an attempt was made to help workers, he came down on the side of industry.

“We start out as liberal-minded people,” said McTeague, who served three terms as a Democratic representative in the House. “Our view of what a good, fair society is is probably a lot different from what your publisher’s is.”

McTeague called his law firm medium-sized for Maine, and said he and his partners also were contributing to Attorney General James E. Tierney’s Democratic primary campaign for Congress in the 1st District.

Another law firm, Preti, Flaherty & Beliveau, with some prominent Democrats as partners, gave Brennan a total of $6,000. Attorneys Albert Beliveau, Severin Beliveau, Anthony Buxton, Harold Pachios and Jonathan Piper each gave $1,000 while attorneys Michael Gentile and Bruce Gerrity gave $500 apiece.

Cable TV companies also went for Brennan in a big way.

Tom Steel of the New England Cable TV Association said cable TV companies felt Brennan would be more sympathetic than McKernan to protecting cable-TV firms from competition by telephone companies.

“If phone companies can compete with cable directly that means the end of cable TV,” said Steel.

Better Cable TV of Waterville, Cablevision Systems Corp. of Woodbury, N.Y., and Public Cable Co. of Portland each gave $2,000 to Brennan. Cable Television of the Kennebunks, New England Cable TV Association, Paragon Cable of Caribou, State Cable TV Corp. of Augusta and United Video Cablevision of Portland each gave $1,000.

For McKernan, Maine oil companies were major donors.

Webber Oil Co. and Dead River Co., both of Bangor, each gave McKernan $5,000. Larry K. Mahaney, president of Webber Oil, and Danville Webber each gave $1,000. C.N. Brown Co. of South Paris and Brunswick Coal and Lumber, an oil dealer, each gave $2,000.

Construction companies and real-estate firms gave to both campaigns.

Some donors covered their bets by giving equal amounts to both candidates.

UNUM Insurance Co. in Portland gave $5,000 to both Brennan and McKernan. The Bangor law firm of Eaton, Peabody gave $1,000 to both candidates. So did Albert LePage of LePage Bakeries in Auburn.

Maine law limits individuals to contributing $1,000 in both the primary- and general-election campaigns, or a total of $2,000 per candidate in any campaign. Corporations, associations and political-action committees can give $5,000 in both primary- and general-election campaigns, or a total of $10,000.

In a loophole that has been criticized by Maine Common Cause, individuals can give more than the $1,000 limit by giving in the name of spouses, other relatives, or subsidiary companies.

McKernan got contributions of $1,000 or more from 97 individuals and groups, while Brennan got 179 contributions of $1,000 or more.

Reports on file with the Maine Commission on Governmental Ethics and Elections Practices also show:

McKernan got $5,000 from Speedway Inc. of Oxford and $1,000 each from three members of the Bahre family, former owners of Oxford Plains Speedway who now are building an auto speedway in New Hampshire.

“We like the man. He’s done a good job. He’s very, very capable,” said Gary Bahre.

Brennan benefited from the generosity of the Dunfey family. John Dunfey and William Dunfey, both developers in Portsmouth, N.H., each gave $1,000, as did Robert Dunfey, a South Portland developer, and Jerry Dunfey, a Boston hotel executive.

James Mundy and wife Donna Mundy canceled each other out with their $500 donations to Brennan and McKernan, respectively. Mundy is the former chairman of the Maine Human Rights Commission who recently tangled bitterly with McKernan over the issue of equity for women in the schools. Donna Mundy is a UNUM executive and president of the Maine Chamber of Commerce and Industry.

Richard J. Warren, publisher of the Bangor Daily News, gave McKernan $500 and Joanne J. Van Namee, chairman of the board of the Bangor Daily News, gave $400 to McKernan.

Jane Smith of Manchester, mother of the late Samantha Smith, gave $200 to Brennan.

The Association for the Advancement of Psychology in Colorado Springs, Colo., gave $2,000 to Brennan.

White Rock Distilleries of Lewiston gave $1,000 to McKernan; Anheuser-Busch gave $5,000 to Brennan.

Douglas H. Brown, retired owner of Doug’s Shop ‘n Save Supermarkets; Leon Gorman, president of L.L. Bean; Thomas McBrierty, president of New England Telephone; David Hawkes of the Peat Marwick consulting firm; Galen Cole, president of Coles Express; and Thomas Greenquist, president of Bangor Hydro-Electric Co., each gave $1,000 to McKernan. So did C. Douglas Dillon, former secretary of the treasury under Presidents Kennedy and Johnson.

David Moscovitz, former PUC commissioner; Gordon Weil, former state energy-office director; the Hermon Meadow Golf Club; the Myerowitz Chiropractic Center in Bangor; and Barry Hobbins, state senator from Saco and candidate for attorney general, each gave $1,000 to Brennan.