Conservative publisher Richard A. Viguerie of McLean, backed by a coalition of Christian churches, today appeared to have won half of this city's 198 delegates in his Republican bid for lieutenant governor.

Viguerie, who is thought to trail both former state attorney general J. Marshall Coleman of McLean and state Sen. John H. Chichester of Fredericksburg, scored his biggest win on the last day of a series of statewide party caucuses that began three months ago.

Today's caucuses, dubbed "Super Saturday," were held to select more than 500 delegates from Arlington and Roanoke counties, Portsmouth, Norfolk and Virginia Beach for the May 31 Republican nominating convention in Norfolk.

Viguerie, who is making his first bid for public office in Virginia, is one of five candidates seeking the GOP nomination, the only race in either party that is still contested.

Coleman, the party's candidate for governor in 1981, is thought by many party officials to lead in delegate totals. However, under party rules, delegates are not bound to vote for any particular candidate, leaving the race at best a murky insider contest that may be decided only after several ballots by the convention.

A total of 2,000 votes are needed to win. Although as many as 6,000 participants are expected to attend the convention, some will have as little as one-fifth of a vote, making it crucial for the candidates to make sure that as many of their supporters show up as possible.

"It must be torturous for the candidates," said Ted Panteleo, head of the newly formed Christian Unity Political Action Committee here and a supporter of Viguerie.

Coleman and his aides claimed a majority of support in Arlington and Roanoke counties and a strong showing in Norfolk, claims that were disputed by other candidates.

State Del. A.R. "Pete" Geisen of Augusta County, chairman of the House-Senate caucus in the General Assembly, was among the candidates for lieutenant governor addressing party meetings here and in Norfolk.

Geisen said today his best hope is for the convention to go several ballots, a situation in which supporters of Coleman, Viguerie and Chichester would turn to him in a compromise.

A fifth candidate, Washington lobbyist Maurice Dawkins of Alexandria, has said he is running not to win but rather to draw more blacks into the Republican Party.

Dawkins, who is black, received some of the loudest applause today when he attacked Democratic state Sen. L. Douglas Wilder of Richmond.

Wilder, who is also black, is unopposed for his party's nomination. Last week he criticized Wyatt B. Durrette, the Republican candidate for governor, for calling him the "most liberal" candidate ever to seek the number two job and said "liberal" might be seen as a code word to stir up racial fears.

"Black racism is as dangerous as white racism," Dawkins said.

Wilder has challenged Durrette to prove his statements.