Common Cause and other leading public interest groups tonight are demanding Congress fix this nation's broken campaign finance system. They are asking Congressional candidates to support comprehensive, public financing of election campaigns. They say it's finally time to put the public interest ahead of corporate interests.

Lisa Sylvester reports.

(BEGIN VIDEOTAPE)

LISA SYLVESTER, CNN CORRESPONDENT (voice-over): The disgraced former members of Congress, the lobbyists who bought them, the lawmakers who remain under a cloud of suspicion. They show a political system in Washington out of control. And Congress refuses to reign in the influence pedaling.

MARY BOYLE, COMMON CAUSE: Right now we have special interests that are controlling the agenda. It's their voices that are being heard, because they are giving all the campaign contributions. We think it should be the public's voice.

SYLVESTER: A group of watchdog organizations has launched a campaign to convince candidates to put voters first, ahead of special interest groups. Three hundred and fifty-nine candidates so far have signed a pledge to clean up Congress by supporting spending limits and public funding for campaigns, setting new restrictions on gifts by lobbyists and fully disclosing lobbyist contributions.

John Sarbanes is running for Maryland's third district. He has signed on. So has his opponent, John White, who has not taken a dime from political action committees.

JOHN WHITE (R), MARYLAND CONG, CANDIDATE: At least people in my district will know I'm not beholden to anyone. No ones hand is in my pocket. And I don't have a black book of people that I owe money to.

SYLVESTER: The pledge list includes Democrats and Republicans. But challengers far outnumber incumbents, by at least three to one.

BOYLE: It's a hard sell for elected officials because they are comfortable and they trust in the system that brought them there.

SYLVESTER: But it's a system that has served the few and not the many.

(END VIDEOTAPE)

SYLVESTER: Common Cause is singling out and candidates who are running on a reform Washington platform but have not signed the pledge. One example, Michael Steele. He's running for a Maryland Senate seat. His campaign has featured several anti-lobbyist ads, but he has not signed the pledge after repeated invitations. And his campaign office did not return our calls -- Lou.

DOBBS: Yes, I have to say, in my opinion, Common Cause is taking on this issue at a critical time when the public interest does need to be served. The entire country has to look at the idea of clean elections, public financing, because it is the only money available that would be a countervailing influence in a political system that is now absolutely dominated by corporate America.

Lisa Sylvester, thank you very much.