Vice-Chairwoman Ellen Weintraub, a Democrat, disagreed. "I've always been clear we shouldn't change rules in the middle of an election," she said. "If you find things you don't like, you fix them for the next cycle so they don't happen again."
After the decision, Sens. John McCain (R-Ariz.) and Russell Feingold (D-Wis.), authors of the 2002 campaign finance reform law, issued a joint statement lambasting the FEC and saying it had not done its job.
"By refusing to take action today on the soft money activities of 527 groups, the commission has failed to close a loophole that dangerously undermines the purpose of the federal campaign finance laws," the senators said.
"As a result, a flood of soft money will enter the system which will violate the letter and the spirit of the law."
But Ellen Malcolm, president of America Coming Together, said that if McCain and Feingold had wanted to restrict 527s, they should have "passed that in the law."
Commissioner Danny McDonald, a Democrat, suggested that if Congress disapproved of the FEC ruling Thursday, it could immediately rectify the situation by enacting new legislation. "It may well be we don't have a fix on what Congress intended," he said.
Republican consultant Craig Shirley said he believed conservative groups would now "move pretty quickly to try to compete" with the Democratic-leaning 527s. "Our money was on the sidelines until we got a clear understanding of what the FEC was going to do," he said.
David Keating, executive director of the Club for Growth, a 527 that this week announced it was launching a television ad campaign on behalf of Bush, predicted that his group would now spend more than $10 million on the presidential race.
"It could even be double that," he said. "The only limit is how much money we can raise."
Despite the liberal groups' edge in the soft-money race now, America Coming Together's Malcolm said she believed that overall, Republicans would still spend much more than Democrats come November. Democratic insiders formed the 527s last year when they feared that the party and its presidential candidate would be unable to raise enough in individual "hard-money" contributions to be competitive with President Bush and the Republicans.
Under federal law, such contributions to presidential candidates are limited to $2,000 per individual. Traditionally, Republicans have far outraised Democrats in these donations. Bush, for instance, has raised more than $180 million for his reelection bid, while Kerry has collected about $80 million.
Wes Boyd, who helped found MoveOn.org, praised the FEC decision.
"It's not the FEC's job to regulate issue organizations," he said. "The flap was an attempt by the Bush campaign and the Republican National Committee to regulate opposition to administration policies....It's a case of Goliath demanding that all slingshots be banned."
Times staff writer Nick Anderson contributed to this report.