Herbert Harris II and Joseph L. Fisher were not on anyone's ballot Tuesday.

But with the election of Democrat Charles S. Robb and his running mates, Harris and Fisher, former Northern Virginia Democratic congressmen, are once again acting like candidates for whom next November cannot come soon enough.

"I was impressed beyond belief-- and, if the word doesn't sound trite, inspired -- at the number of people who were willing to start thinking about and talking about the congressional campaign this early," Harris said yesterday.

Fisher, greeted at an election night party with cries of "We Want Joe," had been unclear about his intentions. But after Tuesday's Democratic success, he said, "I am leaning very much toward running again . . . . Obviously, the events of this Tuesday are encouraging."

Scores of Harris campaign workers collected signatures at the polls and passed out buttons urging Harris' return to Congress in 1982. Harris himself dashed from Alexandria to Fairfax to Prince William to attend Democratic victory parties and drop hints about his own coming campaign.

"We kind of discouraged that," said Prince William Democratic chairman G. Richard Pfitzner, saying he feared Harris' election day efforts could have harmed the Democratic ticket. "Herb evokes some strong feelings in everybody -- either you love him or you hate him," he said, "and Chuck (Robb) was going for some people down the middle of the road."

But both Harris and Fisher hope the Democratic sweep signals a growing disenchantment with the Reagan administration that could help them next year.

Republican Reps. Stanford E. Parris, who beat Harris in 1980, and Frank Wolf, who unseated Fisher last year after two earlier unsuccessful attempts, both said Tuesday's Democratic success would not affect their races. Robb's solid win was not a referendum on Reagan since Robb never criticized the president, they said. And they pointed to Republican attorney general candidate Wyatt Durrette's success in Northern Virginia despite his statewide loss.

But Parris supporters are worried about the loss of moderate Republican Del. David Speck in Alexandria. The success of the state Democratic ticket can only hurt, they say, especially if Robb concentrates on rebuilding the Democratic Party in his conservative image at the local level.

In addition, Parris will have to run in a district that was redrawn by a Democratic General Assembly last year to Parris' disadvantage. The assembly lopped off western Prince William, Republican territory where Parris' 2,600-vote plurality exceeded his total winning margin of 2,100 votes.

Parris also will not have the same long coattails next year that Reagan provided in 1980. While Parris was carrying his district by 2,100 votes, Reagan rolled up a margin of 42,000 votes.

Harris and Parris are personal and ideological rivals who have faced each other twice. In 1974, Harris rode the anti-Watergate backlash to turn Parris out of office. In 1980, Parris returned the favor. The 1982 campaign is likely once again to be bitter, expensive -- and close.

"There is definitely a strong sentiment out there for a change," Harris said. "Because of the meat-ax approach in federal employe layoffs -- especially in the energy and environment areas -- I don't think the administration realized the actions appeared to be quite as ruthless as they did."

About 30 percent of the households of the 8th District have at least one federal employe. But half of those work for the military, a Parris spokesman said, and by no means all of them are unhappy with Reagan -- or Parris.