A FEW SHORT months after its passage in Congress, and just days after taking effect, campaign finance reform is under threat. A complaint filed last week by reform advocates before the Federal Election Commission explains why. The purpose of the law was to eliminate the influence in federal elections of unregulated "soft money" donations to political parties -- those $100,000-and-up checks that have increasingly been corrupting U.S. democracy. Yet in the run-up to the law's taking effect, both parties raced to create new organizations to receive the same old uncapped contributions. The complaint focuses on two of these groups. One is the Leadership Forum, led by a former aide to Republican House Majority Leader-elect Tom DeLay and a former chairman of the National Republican Congressional Committee; the committee , in fact, gave the group a nice little baby-shower present of $1 million of its soft money. The other is the Democratic State Parties Organization, a creature of the Democratic Party composed of state party committees. Party leaders are, of course, not formally involved, but they have made clear that the groups are favored addresses for continued soft-money giving. If the Federal Election Commission does not stop this, the McCain-Feingold reform will be undermined and the soft-money system will persist.

Unfortunately, it is hard to have confidence that the FEC will respond aggressively to a naked effort to circumvent the core purpose of the reform law. To the contrary, the rules the FEC adopted to implement the new law aid the parties in their end run. The law does not merely forbid national parties to raise and spend soft money; it applies the same strictures to any group that the national parties "directly or indirectly establish, finance, maintain, or control." Yet the FEC's interpretation of this restriction seems calculated to tolerate the creation by the parties of entities capable of continuing the soft-money hunt. Specifically, the commission will decline to consider evidence of coordination between a party and another fundraising entity if the coordination occurred before the effective date of the law, Nov. 6. The ostensible idea was to prevent long-established groups with some historical tie to a party from being forever tainted as party-established committees. But the rule is written far too broadly and seems to require the commission to turn its gaze from deliberate party efforts to reestablish the soft-money system in another form -- as long as the job was done before Nov. 6.

The groups here may be so flagrant in their efforts that they will run into problems even under the FEC's grandfathering rule. The Leadership Forum's million-dollar donation, in particular, seems improper even under the commission's very generous reading of the law. Still, the watchdog here dozes most of the day. The long-run answer is to replace the commission with an enforcement mechanism that is both structurally freer to act and not reflexively sympathetic to the groups it regulates. In the meantime, the FEC should act quickly and decisively to avoid creating a precedent that would make the law's strictures so easy to bypass that the entire regime would become meaningless. It should do its job, in other words, and not knowingly tolerate the subversion of Congress's will.