THE VOTERS have spoken just about everywhere they will speak in what is the most off of off-years. Do the results, taken together across the nation, tell us anything about where the country is going? Superficially, they say it's going Democratic. The three governorships up this year -- Louisiana, Kentucky and Mississippi -- were all captured by Democrats, but the trend was not terribly partisan. These are all historically Democratic states, and you could argue the trend was, mildly, toward the Republicans: governor-elect Buddy Roemer of Louisiana has had one of the least Democratic voting records of congressional Democrats, and governor-elect Ray Mabus of Mississippi saw his lead shrink rapidly as Republican Jack Reed suggested he'd need new taxes to keep his education promises. The Democrats need to carry states such as these to win the presidency in 1988. But the 1987 results, by themselves, don't give them any confidence they can do so.

What we find relevant about the contests in all three of these states is something else. In two of them the incumbent governor was retiring, as President Reagan is next year, and in Louisiana the governor was badly disabled by scandal. Voters had to choose there, as they will have to choose nationally, a new leader from a field of candidates they mostly knew little or nothing about. For months they seemed to be all over the lot: the polls showed low and stable percentages for a whole bevy of candidates.

Then all of a sudden opinion moved and moved quickly. In the Democratic primary in Kentucky, tens of thousands of voters a day shifted to Wallace Wilkinson, a Lexington businessman who had never held office. He soundly beat former governor John Y. Brown Jr. and Lt. Gov. Steve Beshear; his victory in the general election Tuesday was anticlimactic. In Louisiana Gov. Edwin Edwards had a narrow but constant lead in the polls for months. Then Buddy Roemer zoomed up from fourth or fifth place and won so soundly that Mr. Edwards, in second place, quit the field. In Mississippi the late movement was away from Ray Mabus and toward Republican Jack Reed, though it was not enough to elect him. The moral for the presidential race is: don't pay too much attention to today's polls. Voters are not anchored to their choices, and as they learn more about the candidates and the issues they're liable to move toward and away from candidates very rapidly.