ASHINGTON - A 20-year effort to revamp the nation's campaign-finance system failed again yesterday as a Republican-led filibuster thwarted a majority in the Senate from advancing the landmark initiative.
To the dismay of election watchdog groups, the legislation's defeat cleared the way for the national political parties to raise and spend hundreds of millions of dollars in largely unregulated, special-interest contributions in the 2000 campaigns. The same type of ''soft money'' donations were at the heart of numerous corruption charges stemming from the 1996 elections.
In back-to-back roll calls, the Senate foes of soft money fell short of the 60 votes needed to break a filibuster on two measures that would have altered the way US elections are financed.
President Clinton and leaders of the movement to change the system, including Republican Senator John McCain of Arizona, vowed to press on. Senate Democrats immediately began a parliamentary effort to force definitive votes on the soft-money ban and a more comprehensive overhaul plan, while Republicans were poised to block the effort on a party-line vote today.
''The failure of the Senate to adopt real reform is a victory for the politics of cynicism, and it leaves unchecked the influence of moneyed special interests,'' Clinton said. ''The people of this country want reform, and the Senate cannot stand in their way forever.''
But the Senate majority leader, Trent Lott, who controls Senate procedures and opposes changing campaign-finance laws, predicted in a news conference that the effort to alter the system before the 2000 elections was destined to fail. ''It's dead for the year,'' Lott said.
The filibuster's leader, Kentucky Senator Mitch McConnell, defended his parliamentary tactics as a battle to preserve the democratic process. Citing court rulings that have equated free speech with the freedom to donate money to political causes, McConnell praised his Republican colleagues ''who resisted the temptation to support a measure that would have quieted the voices of American citizens and destroyed the effectiveness of our national political parties.''
McConnell, the chief fund-raiser for Senate Republicans, noted that an effort to end a similar filibuster last year also fell eight votes short. And he asserted there ''is no momentum whatsoever for this kind of measure that seeks to put the government in charge of what people say and when they may say it.''
Still, McCain, who was the chief Republican sponsor of the bill, said he will ''persevere'' and will try to attach the proposed ban to other legislation before Congress adjourns.
In killing the initiative for the fourth straight year, the Senate voted, 53-47, to cut off the GOP-led filibuster on the proposed soft-money ban, seven votes short of the 60 necessary. An attempt to short-circuit a filibuster on a more comprehensive overhaul plan failed, 52-48, eight votes short.
The House had passed the broader measure, which also would have banned soft money, 252-177, and Clinton had vowed to sign the bill into law in time to change the rules for the 2000 elections.
The votes marked the 20th time since 1987 that GOP leaders have killed campaign-finance changes by filibuster, a tactic they have used since 1979 to block efforts to overhaul the system.
The ''bill was again blocked by the pre-Halloween trick-or-treat parliamentary maneuverings of reform opponents,'' said Scott Harshbarger, the president of Commmon Cause and former Massachusetts attorney general, who saw promise for the movement despite the setback.
''What a farce,'' Senator John F. Kerry said on the Senate floor of the filibuster tactics. ''What a joke to pretend somehow that the US Senate has done anything serious on campaign finance reform,'' said Kerry, a supporter of revamping the system.
Senator Edward M. Kennedy called it ''a disgrace that the Republican leadership is resorting to a filibuster to maintain the corrosive power of special-interest money and block this needed change.''
Joining all 45 Senate Democrats in supporting the proposed ban on soft money were eight Republicans, including Senators Olympia J. Snowe and Susan M. Collins of Maine, and James M. Jeffords of Vermont.
Voting with every Senate Democrat on the more comprehensive proposal were seven Republicans, including Snowe, Collins, Jeffords, and Senator John H. Chafee of Rhode Island. The broader bill also would have restricted ''issue ads'' financed by soft money and run by independent groups that are not required to disclose the source of their funds.
Supporters of the soft-money ban argued they had made progress by picking up three more GOP backers: Senators William V. Roth Jr. of Delaware, Sam Brownback of Kansas, and Tim Hutchinson of Arkansas. But two other Republicans who have previously supported campaign-finance legislation - Chafee and Senator Arlen Specter of Pennsylvania - opposed the soft-money ban in favor of the more sweeping alternative.
Although the net gain was a single vote, the measure's chief sponsors - McCain and Senator Russell D. Feingold, a Wisconsin Democrat - said they will continue to try to reduce the influence of special-interest money in politics.
''No matter what parliamentary tactics are used to prevent reform, no matter how fierce the opposition, no matter how personal, no matter how cycnical this debate remains, the senator from Wisconsin and I will persevere,'' said McCain, who has made the issue the cornerstone of his campaign for the Republican presidential nomination.
As Texas Governor George W. Bush sprints ahead of his rivals in the presidential fund-raising race, McCain yesterday picked up an ally in the GOP field, as Gary Bauer offered partial support for the soft-money ban. Bauer urged McCain in a letter to beef up elections laws by requiring unions to obtain permission from their members before using their dues for political purposes.
Bauer's proposal, a popular theme among Republican leaders, is strongly opposed by Clinton and congressional Democrats.
