DID RICHARD GEPHARDT win in Iowa by spending more money than federal law permits? Has he or anyone else exceeded the state spending limits in Iowa or New Hampshire? A lot of political pros think that the Gephardt campaign and maybe others have overshot the $775,000 spending cap. When you add the cost of the Gephardt Iowa media blitz, which started Dec. 26 -- about $500,000 -- to the campaign's other expenses (more than 100 paid staffers, lots of telephone banks, candidate travel), you get numbers that look uncomfortably high. Final reports on January spending are not due at the Federal Election Commission until Feb. 20, and the final February reports are due a month later. But the Gephardt campaign has already announced it will claim 50 percent of the cost of its television ads as fund raising, which is exempt from the limit, because one word at the end of the ad asked Gephardt supporters to contribute; and it's possible that only that claim will keep his spending total below the cap.

This should strike most people as nonsense. Yet in 1984 the FEC, in one of those cases that has earned it a reputation as a toothless tiger, allowed John Glenn's campaign to count only half of a media buy against a state spending limit. The state spending limits don't make much sense as campaign finance law. But they're on the books and should be strenuously enforced. Otherwise the least scrupulous and the most legally adventurous of campaigns have an unfair advantage.

So far as we know, no one has filed a complaint with the FEC against the Gephardt campaign, and the FEC won't take notice of a possible violation until it has the full spending reports for Iowa -- these come in after 30 more states have voted. Even if another campaign files a complaint, the FEC must allow 15 days for a response, and its secrecy rule gives campaigns an incentive to drag out negotiations about a penalty.

Fortunately, managers of Albert Gore's campaign have figured out a faster way to get an answer. They've asked the FEC for an advisory opinion about whether they can charge off 50 percent of the cost of an ad for fund raising because of just one word. The FEC is required to give an answer in 20 days. If the answer is no, as common sense suggests it should be, then Mr. Gephardt's campaign and Michael Dukakis', which has used the same device, should amend their reports. If that puts them over a state spending limit, they should confess they've violated the law and pay a reasonable fine. No campaign should profit by violating, even unintentionally, a rule that other campaigns have scrupulously observed.