THE HOUSE Democrats have voted in their man, Francis X. McCloskey, as the congressman from the 8th district of Indiana. The vote, with the exception of a few dissenting Democrats, was entirely along party lines. There's a certain inevitability to this. The technical issue the two sides narrowed the issue down to -- whether unnotarized, unwitnessed absentee ballots that had been retained by county clerks in allegedly secure conditions should be counted -- is not one on which most politicians have strong views. Democrats tend to decide it in the way that will seat the Democrat, Republicans in the way that will seat the Republican.

Even so, we continue to believe that the Democrats, and now the House, did not resolve this issue the right way. You can accept, as we do, the scrupulousness of their task force's vote count and the good faith with which it approached its job and still believe, as we do, that when the margin is so narrow, and the decision on which ballots should be counted hangs on fine judgments on which reasonable minds may differ, the correct decision would have been to declare the seat vacant and allow the governor of Indiana to call a special election. Mr. McCloskey holds the seat now under a cloud. Many of his colleagues and his constituents believe he holds it illegitimately. For that he will, fairly or not, be held responsible by his colleagues in deliberations in the House and by his constituents if he seeks another term in 1986.

This was a close election and the House, contrary to what some Republicans have been saying, does have the right to look behind a state's election returns and to determine for itself who actually won. But the majority is not always politically wise to do so. The Democratic leadership decided early to challenge what it cnsidered, with some reason, to be a fishy result in Indiana. That put it in a political no-win situation: if it ruled for the Democrat, it would inevitably arouse the partisan rancor we see now; if it ruled for the Republican, it would erode the loyalty of some House Democrats.

The Republican leadership, and not just because it was goaded by rebellious younger members, chose to treat this dispute as a matter of high constitutional principle. But it's not, and now Republicans are faced with an unpleasant choice: they must either pull in their horns and not make good on their threats of disruption, or they must concentrate on an issue which is of little interest to voters to the exclusion of issues which could actually gain votes for Republican candidates. This is not a situation in which anyone on either side of the aisle has behaved dishonorably. But it is one in which many people on both sides of the aisle have, to varying degrees, used bad political judgment.