A senior Northern Virginia Republican politician recently summed up the race for his party's nomination in the 8th Congressional District.

"The 8th District," he said, "is becoming a laughing stock in Richmond. That's the posture these clowns have put us in."

The candidates themselves, however, are taking things somewhat more seriously. This last week before Tuesday's primary has been filled with a telephone blitz of targeted precincts, a flurry of direct mail pleas for votes, and a retreat, in some quarters, from the gentlemen's agreement among the three candidates that earlier made Democratic incumbent Herbert E. Harris, not each other, the target of their attacks.

In a race between a flamboyantly outspoken County Board chairman, an ultra-conservative minister, and a state legislator more renowned among his colleagues for his absences than his presence, the Republican primary has prompted fears among some party veterans that the race has become more a caricature of one end of the political spectrum than of mainstream voter sentiment.

After many candidates' nights before handfuls of party stalwarts, Fairfax County Board Chairman John F. Herrity, and General Assembly Delegates Robert L. Thoburn and Robert E. Harris are all relying on the U.S. mails and the telephone wires to get their message across.

Robert Harris said that his organization is calling voters in 30 precincts a night and often finds beleaguered households that have already been contacted that evening by at least one of his opponents.

Herrity has sent "three or four" mailings this week to different groups of voters in the far-flung district, which includes Alexandria, Prince William County, Manassas, Manassas Park, northern Stafford County and southern Fairfax County. His mailings included one written by Herrity's 18-year-old son Patrick. In it he tells approximately 1,000 newly registered young voters in Fairfax, that while he understands their preoccupation with high school graduation, they should take a minute to consider his father.

Thoburn also has been concentrating on his direct mail efforts, directing some to all registered voters, some to Republicans, and beginning at least one letter with a folksy approach that tells about how Thoburn got up at 4:30 a.m. to write the letter.

"I got back a letter from one man who said he didn't care what my sleeping habits were or where I was from," Thoburn said, "but he did say he would vote for me."

Thoburn's campaign organization has impressed some party veterans mightily, while frightening others. An ordained minister and self-proclaimed ultra-conservative. Thoburn came out of political obscurity two years ago to make his first bid for the Republican congressional nomination. He lost by fewer than 200 votes.

Now a state delegate, Thoburn is given a strong chance of winning this primary both by supporters and opponents.

Thoburn, said one Veteran Northern Virginia Republican Party official, "has got a built-in base among the 'born again' Christians, the antiabortion people and some other one-issue groups, and he's expanded on that," he said.

"But I don't know if he can win it in a general election," the observer continued. "This is a guy who's proud of the fact that he was the only delegate to vote against the (Virginia state) budget. I think he's so bound by principles that he can easily painted into a corner."

Other party veterans worry about Thoburn's effect on party politics. "I think it should scare the hell out of people if Thoburn gets the nomination," said one politician. "Up here we need all factions of the party - if one faction that extreme becomes the standard bearer, it's going to do to us what (Geroge) McGovern did to the Democrats."

Fairfax County Republican Party chairman Joe Ragan, however, is "not at all sure that he (Thoburn) will be a detriment to the party."

Ragan said that according to a poll commissioned last February by the Republican National Committee, "one of the largest groups that (Herbert) Harris gets support from is conservative Republicans. We think there's an obvious perception problem involved and somebody as conservative as Thoburn could be just the one to correct it."

Ragan recently called Thoburn the front-runner in the campaign, contending that the predicted low turnout in the election would work to Thoburn's advantage.

The Republican Harris, meanwhile, is confidently predicting his own victory. "I'm number one right now, there's no doubt about it. Our phone banks are operating extensively and I really know what's going on, you know what I mean."

Nevertheless, Harris said, he has done three polls throughout the campaign and 30 percent of the voters, he contends, are still undecided. "Really, it's still a crap shoot," he said. "The real battleground is Fairfax County."

In an attempt to throw the political dice in his favor, Harris' mailings have included a tabloid publication that "lists our attributes, of course, and contrasts our candidacy with the others just a bit, if you know what I mean."

What he means, Harris said, is that Thoburn is "just much too narrow and rigid," while Herrity "doesn't have a good grasp of the issues" and, as a public speaker, is "absolutely atrocious."

Thoburn now says that "if I made any mistakes it was in not attacking the positions of my opponents. I think the public is fed up with waffling politicians." Thoburn agrees with Harris' assessment of Herrity, but places Harris himself in the waffling politican category. Harris, he said, "is all over the cabbage patch on the issues."

Herrity, on the other hand, has made no public comments on his adversaries, has no comment on their assessment of him and has forgone the usual politician's privilege of forecasting his own victory.

"Apparently there is not going to be a heavy turnout, which would have favored me," Herrity said. "I don't think there's any way of predicting this one. Frankly, it's all going to depend on who does the best job of getting his vote out on Tuesday."

Herrity does agree that if he is defeated in Tuesday's election, it may mean the end of any political ambition beyond the chairmanship of the Fairfax County Board, which he has held since 1976. Asked if he would make another try for the seat if he lost, Herrity said, "I would seriously doubt that. Frankly, I think the job I have now is as important as any in the country."

Nevertheless, Herrity said, "the two biggest lies in the world are 'The check is in the mail,' and 'I will never seek political office again.'"

A wild card in the deck that will decide the Republican nominee is the number of Democratic voters who may come to the polls, either to vote for a $16 million bond referendum that would be used to build new storm drainage facilities and fire stations or to vote in the Republican race.

Any registered voter can vote in the primary and with a low turnout, Robert Harris contended, all they (the Democrats) would need is 2,000 votes and they could preselect a candidate."