THE DEMOCRATS' prospective presidential nominee, Sen. John F. Kerry, has decided, after some deliberation, to accept his party's nomination when it is offered. But his well-reported dalliance with the notion of delaying acceptance in order to be on a more even financial playing field with President Bush raised another question. No, not the quadrennial one of why bother to hold a convention at all, but the narrower, related question of whether taxpayers should continue to underwrite these four-day infomercial/shrimpfests.

Each major party will receive close to $15 million in federal funding to stage their events. This public financing scheme was adopted after Watergate in response to abuses like International Telephone & Telegraph Corp.'s secret $400,000 contribution to the 1972 GOP convention to get the Justice Department to drop its antitrust complaint against the company.

But the public money doesn't come close to covering the tab. In 2000, for example, the GOP convention in Philadelphia cost $75 million, of which the feds paid only $13.5 million. The Democratic convention in Los Angeles cost even more: $85 million, according to a study by the Campaign Finance Institute. Cities and states hoping to promote tourism and boost their economies pick up part of the bill. But, thanks to loopholes carved out years ago by the Federal Election Commission, corporate money has seeped back into convention financing at a level that makes ITT look chintzy. Private contributions to the convention city's "host committees" have grown from less than $1 million per party in 1980 to $20 million for Republicans and $36 million for Democrats in 2000, according to the CFI. This year the Republicans expect to collect some $64 million for their New York City bash and the Democrats $36 million for their Boston party. The Boston host committee's Web site lists 11 $1 million donors.

The new campaign finance law put such big donations off-limits for political parties, but it didn't cover contributions to "host committees." The argument for permitting such contributions has been that they are designed "chiefly to promote economic activity and good will of the host city," as the FEC put it. But it's silly to think that this giving is done without any hope of political benefit.

As with the rest of the presidential financing system, the convention funding rules need to be overhauled, and lawmakers should consider whether checks of this size are healthy for the political process. Party officials argue that conventions as we know them couldn't be held without permitting this money; we will resist the obvious retort. In any event, it's clear that federal convention funding no longer fulfills its purpose of keeping private money out. That $30 million could be put to better use.