One surprising result of last week's primary election in Prince George's County -- when lines were drawn for a November fight for eight of the nine county council seats -- was the replacement of incumbent Democratic party regulars by nominees self-styled as "independent Democrats."

It may strip the generally underdog Republican nominees of their most potent charge, that Democrats engage in machine politics.

In the 1st District, incumbent Democrat Frank P. Casula, 62, says he's not worried about the upcoming campaign. He maintains that "If you do your job right, you don't have to worry."

Casula, one of only four Democratic council incumbents seeking reelection, will campaign on his record of constituent services, aides say. His Republican opponent, John Ritchie, 38, the owner of a construction equipment firm, charges Casula with not having "the knowledge to deal with the major issues of the 1980s."

In the 2nd District, Democratic nominee Anthony Cicoria, a state delegate who owns a bowling trophy store, is being challenged by W. Michael Zane, a management recruiter from Hyattsville. Zane, a last-minute entrant in the primary, considers himself a "Mac Mathias Republican," with moderate leanings, and plans to spend less than $100 on his campaign.

Zane says his biggest concern -- as a candidate in a district that has a large number of older residents -- is the conversion of rental apartments to condominium ownership. But those same senior citizens constitute Cicoria's strongest constituency, the voters who helped him beat Hyattsville mayor Tom Bass in the primary. Both Cicoria and Zane oppose lifting the county's TRIM property tax limitation because of the economic burden it would place on elderly residents with fixed incomes.

In District 3, newcomer James Herl, an aide to council member Casula, says he is an independent Democrat, but Republican Joseph R. Drewer hopes to persuade the voters otherwise.

"When you've been weaned by Winnie Kelly for three years," asked Drewer referring to the former Democratic county executive Winfield Kelly, "and then you get trained by Frank Casula, where do you get independence?"

Herl, the unofficial victor over veteran infighter Thomas Hendershot -- by only 46 votes -- favors modifying the TRIM property tax limit, but not if it would mean an increase in taxes on existing single-family homes. Drewer says he opposes any change in TRIM now.

In District 5, Greenbelt Mayor Richard Castaldi, 37, faces Republican Kenneth D. Powell, a 22-year-old graduate of the University of Maryland. Castaldi won the Democratic nomination when his three opponents from the city of Bowie split the vote in that area. Castaldi can be expected to repeat a strong showing in Greenbelt, which has always felt underrepresented. Powell could not be reached for an interview.

The county's biggest primary surprise came in District 6, which stretches from District Heights to Largo, when school board member Jo Ann Bell defeated incumbent council chairman Gerard McDonough, a power in the Democratic Party. As a result, her opponent in the general election, Republican Wilbert Wilson, will be focusing on the record of the school board, which spends 60 percent of the county budget, instead of McDonough and "machine politics."

Bell supports modifying the TRIM tax limit, "only if it does not overburden homeowners." Wilson said his polls show that voters in the district opppose modifying TRIM, even if it means laying off teachers.

Wilson says that the board of education has mismanaged its budget, and was unwilling to take a hard line on spending cutbacks other than teaching jobs.

Bell responds that if there is fat in the system, "I've never heard Mr. Wilson come forward and say where. I'd be glad to answer any specifics he had."

Meanwhile, Bell, a 44-year-old homemaker, says she will remind voters that County Executive Lawrence J. Hogan, Wilson's boss, pushed massive cuts in the current school budget.

Two newcomers will contest the predominantly black 7th District in the Suitland area. Mel Wiliamson-Gray, president of the county Black Republican Council, opposes Hilda Pemberton, deputy personnel director of the Prince George's Hospital Commission. Pemberton ran with the support of regular Democrats and the Chamber of Commerce.

Gray faces an uphill struggle to justify her Republican affiliation with largely Democratic black voters.

The campaign in the 8th District pits Joseph Johnson, the only registered independent in the council races, against Prince George's best known "independent" Democrat, council member Sue V. Mills. Johnson was the tenacious leader of a successful 1980 referendum that created this year's single-member council districts -- over the opposition of most Democratic leaders in the county. A longtime resident of Clinton and a friend of Mills, he shares her "grass-roots" style.

In the 9th District, Democratic incumbent William B. Amonett takes on Ella Ennis of Brandywine, who has been preparing for this election for more than a year. Ennis, a former legislative liaison for the county executive, has been unrelenting in her attacks on alleged "Democratic machine bosses," particularly during the drawing of the new council districts. Amonett, a real estate broker, ran with the backing of the incumbent Democratic state senators and strong support from the business community.