CAN THE federal elections laws work as they should? That question is raised by a complaint filed with the Federal Election Commission Oct. 22 by the Democratic Congressional Campaign Committee.

The subject of that complaint is the father-son TV ad the National Republican Congressional Committee is airing on 120 TV stations covering 39 states. The Democrats charge that the ad, by urging a vote for the Republican congressional candidate in the viewer's district, amounts to a contribution-in-kind to that candidate. Since in most cases the NRCC has already contributed the maximum allowed by law, any such contribution-in-kind would be illegal -- and unfair besides. The Democrats add that the Republicans are targeting mailings of 50,000 letters in dozens of close districts -- a practice which, with the TV ad, constitutes illegal aid to their candidates. In reply, the Republicans say their ad is perfectly okay. It doesn't mention any candidate by name, not even Ronald Reagan or George Bush, and it makes arguments applicable to Republican candidates generally. If that's not an entirely proper "generic" ad, they ask, what is?

What is troubling about this controversy is that it hasn't yet been resolved. The FEC declined to expedite action on it, and even if it had, the NRCC would still have 15 days to respond; the Democrats have gone to court, but in a hearing Friday the judge reserved decision. Yet this is just the sort of case that the FEC ought to decide -- and ought to be able to decide -- rapidly. The facts are not in dispute. The ad is readily available. The Democrats will be hurt if an illegal ad is allowed to be widely broadcast. The Republicans will be hurt if a legal ad is somehow taken off the air.

And in this kind of case, in contrast to the shenanigans that often take place in local campaigns, the parties don't need more time to present their arguments. You can be sure that the national parties have their lawyers examine their ads to make sure they fall within the election laws; often TV networks or stations, to protect themselves, demand legal opinions before they'll broadcast the ad. So it's not for the national parties to respond immediately to the sort of complaint the Democrats have brought here.

The campaign laws should be amended so that such cases can be decided quickly by the FEC. Sometimes there will be close questions, although in this controversy it seems to us that the Republicans are clearly right. But even close questions must be decided soonor or later, and when so much is at stake, sooner is better.