Campaign finance reform advocates are out to prove that the landmark bill passed by Congress last month and signed by the president will not be thwarted and diminished by available loopholes.

Campaign finance torchbearers Sens. John McCain, R-Ariz., and Russ Feingold, D-Wis., are now pushing for an overhaul of the Federal Elections Commission in hopes that it will be leaner and meaner when it comes to enforcing the new laws and blocking existing loopholes. They have not yet outlined details of such legislation.

The latest campaign finance reform bill signed by President Bush in March eliminates all soft money, or unregulated contributions to national political parties, and limits the advertising from special interest groups in the two months preceding election day. It also raised the ceiling on individual campaign contributions.

Sen. Mitch McConnell, R-Ky., who has long opposed such changes to the campaign finance laws, arguing it restricts free speech while benefiting incumbents, has already launched a suit against the legislation on grounds that it is unconstitutional.

He, like others, believes that eliminating soft money contributions to parties will just force candidates and parties to pander more to special interest groups, which will continue to raise the money and find other ways to use it in the campaigns without directly violating the law.

"It will never be over," said the Rev. Timothy O'Brien, a Marquette University political science professor, who said challenges to the law and the amendments that will follow will lead to years of bickering.

That’s why McCain and Feingold are trying to address the problem before the laws are expected to take effect after the election. They are focusing on the FEC, which now has the enforcement powers to ensure that their opponents’ predictions don’t come true.

"We have an obligation to make sure the law — both the intent of the law and the letter of the law — is enforced by them," McCain said Tuesday. McCain then went on to blame the FEC for allowing soft money into campaigns in the first place.

McCain and Feingold, backed by Washington-based Democracy 21, a self-styled government watchdog pushing for an FEC overhaul, said the FEC commissioners — three Democrats and three Republicans — are too close to the political parties they are charged with regulating.

McConnell has already said he would oppose any overhaul that would turn the agency into "speech police."

"The model for the FEC is the same model used for the Senate and House ethics committees," he said. "It is designed to prevent either side from terrorizing the other and to weed out ridiculous complaints, of which the FEC gets a massive number."

Democracy 21 founder Fred Wertheimer said his group also wants Congress to provide public financing for congressional candidates, change public financing for presidential candidates and to find a way to provide free or low-cost TV time for congressional candidates.

"Campaign finance is about the role of money in politics, the ability of money to corrupt democracy," Wertheimer said. "That's an ongoing issue in democracies in countries all over the world for as long as you've had governments."

McCain and Feingold also want to block a bill passed by a House committee that would exempt tax-free groups known as 527s from having to file with the Internal Revenue Service. Known as third-party special interest groups, the non-profit organizations often target specific political issues, parties and in an indirect way, candidates, with large unregulated contributions.

McConnell called the proposal "modest" and predicts little if any action on such bills by Congress anytime soon, while the "reform industry" will continue to make a living off the issue.

"We've spent a disproportionate amount of time on this already and the one thing everyone has in common is campaign-finance fatigue," he said.

The Associated Press contributed to this report.