WHILE VIRGINIA'S candidates for governor remained neck-and-neck in the first heat of the 1981 Political Vacuity Cup Races, voters across the state--well, a handful--slipped away to the polls this week to produce a blanket endorsement of the legislative establishment: when the party primaries ended, unofficial, unsurprising returns showed all but three incumbents to be victors. Only in Northern Virginia, where redistricting and some bitter infighting unseated one member of each party, and Norfolk, where a one-term Democrat lost, was there any change in the status quo.

An opening for change remains, of course, because there is still the general election in November, when the state's philosophically blurry Democratic and Republican parties will try to make enough mild distinctions between themselves to capture the requisite number of voters for victory. But here again, incumbents enter the contests with a premeditated and religiously preserved edge, for it is they who successfully lulled most of the electorate into this political trance in the first place.

Are Virginians all that content with their envoys to Richmond, on whom the crusty constraints of local option laws have concentrated enormous control over localities? We don't know because between redistricting and scheduling, this year's primaries could not have been more poorly timed. As a result, political insights have been more fogged-in than usual.

Members of the House of Delegates knew all too well that their reapportionment plan was so flawed it would explode; couple this with a quick primary campaign and a vote on the day after Labor Day-- and the incumbent lawmakers' design to discourage voter interest could work perfectly.

That could change in this last round. Some voters may decide to pay more attention to the November legislative campaigns simply out of curiosity about what their representatives in Richmond have done for them lately or might do next time. Others may turn to these contests for quite another understandable reason--sheer boredom with the race for governor.