Arlington County Board candidates Stephen H. Detwiler and Mary Margaret Whipple have so far raised $43,705 and $37,716 respectively, making their race for the seat the most expensive in recent years.

Detwiler, a Republican-backed independent and current County Board chairman, has received contributions from 1,193 persons, including 58 who gave $100 or more, John Phillips, his press secretary said yesterday. The Detwiler campaign has spent $38,512 to date.

Whipple, a Democrat and former school board chairman, has received money from 846 persons, including 44 persons who contributed over $100, according to her campaign manager, Lucy Denney. The Whipple campaign has spent $24,243.

Nearly $9,000 of Detwiler's funds came from real estate firms, people with large real estate holdings, developers and two political action committees. The Rosslyn-headquartered National Conservative Political Action Committee (NCPAC) contributed $500, the same amount it gave Detwiler in 1978 when his election tipped County Board control to GOP-backed independents.

The Affordable Shelter Political Action Committee of the Northern Virginia Builders Association, a trade association, contributed $1,000.

The largest individual contributor to Detwiler, executive vice president of Continental Federal Savings & Loan Association, was Andrew M. Barr, a real estate broker, who gave $1,125.

Among his other contributions was $300 from the Preston Construction Corp., owned by developer Preston C. Caruthers. Caruthers, an annual contributor to GOP campaigns, is a member of a partnership seeking County Board approval of their $165 million bid for the rights to develop Court House Plaza.

A bipartisan board-appointed selection panel, however, has recommended awarding the rights to another partnership.

Whipple received a $725 contribution from developer Terry Busby and his wife, Carol. Her largest individual contribution, $920, came from County Board Democrat John G. Milliken. She also received $565 from County Board member Ellen Bozman. The council of the Arlingtonians for a Better County, which has endorsed Whipple, gave $1,000.

Virginia Secretary of Human Resources Joseph L. Fisher, a former 10th District congressman and County Board member, contributed $285.

The candidates disclosed expenses and a those contributing more than $100 through Oct. 22 in a campaign finance reports filed late Monday.