With an overall fundraising advantage from the beginning of the presidential campaign, Republicans moved far more cautiously than Democrats to invest in 527 groups, but with the election just weeks away, groups aligned with the GOP are outspending their Democratic counterparts on radio and television by 6 to 1.

Allies of President Bush have focused the efforts of their 527 groups on advertising, and the two leading pro-Republican groups -- Progress for America and Swift Boat Veterans for Truth -- have played a key role in efforts to undermine Democratic nominee John F. Kerry's credentials as a Vietnam War hero and as someone capable of defending the country against terrorist attacks.

"I'd give the Republican 527s the 'more bang for the buck award,' that's for sure," said Democratic consultant Bill Carrick.

During the spring and summer, two Democratic groups, The Media Fund and MoveOn.org, outspent Republicans on advertising by a large margin. But since late August, Republican 527s running television and radio commercials have raised $48.2 million, compared with $7.8 million by Democratic groups, according to reports to the Federal Election Commission.

Democratic 527s retain an advantage in funding voter registration and turnout. But it is difficult to get an overall sense of comparative spending because much of this "ground war" activity is conducted by churches and charitable groups that do not disclose financing.

Most of the recent money for television has gone to Progress for America (PFA), $35.6 million. The group is run by employees of two allied lobbying and political consulting firms with strong ties to the Bush administration and the Bush-Cheney campaign. The vast majority of its major supporters are leading fundraisers for the Bush campaign, many of whom have earned the designation of "Pioneer" or "Ranger" by collecting $200,000 or $100,000 each, respectively.

Swift Boat Veterans -- started by John O'Neill, and funded by such prominent Texas Republicans as corporate raider T. Boone Pickens Jr. (who gave $1.5 million), investor Harold C. Simmons ($3 million), homebuilder Bob J. Perry ($1 million) -- has raised $10 million.

"We will close strong," said Brian McCabe, PFA president and an employee of the lobbying firm, DCI Group, LLC. PFA was founded by Tony Feather, a partner in the firm as well as a sister company specializing in direct mail that has been paid more than $9.4 million by the Bush campaign and Republican National Committee this election cycle.

Like Democratic activists, Feather and other Republicans tried to anticipate the impact of the McCain-Feingold campaign finance law and build a network of independent groups that would accept large, unregulated "soft money" contributions that the new law prohibited political parties from accepting.

Feather's group, PFA, quickly became known in Republican circles as the organization favored by the White House. PFA held special briefings for donors, and the speakers included Karl Rove, Bush's chief political adviser, and Ken Mehlman, who later became manager of the Bush-Cheney '04 campaign.

The current success of the GOP 527 groups stands in stark contrast to a series of early setbacks. In late 2002, the National Republican Congressional Committee tried to jump-start a 527 called the Leadership Forum with a $1 million contribution, but was forced to take the money back after four watchdog groups filed a complaint with the Federal Election Commission.

In addition, potential donors, particularly corporations, a major source of GOP soft money, were reluctant to give to organizations that might be ruled illegal by the FEC, especially after the Enron and corporate governance scandals.

"Our people were too skittish," said Rep. Thomas M. Davis III (R-Va.), a former NRCC chairman.

Early this year, however, it became apparent that wealthy liberals were giving millions of dollars to such Democratic 527s as The Media Fund, MoveOn.org and America Coming Together (ACT). Top Republicans in the Bush campaign and the RNC reversed strategy and sought to have all soft money-financed 527 activity declared illegal.

On March 30, 2004, the Bush campaign and the RNC filed formal complaints with the FEC against the Kerry campaign and the pro-Democratic 527 groups. "Senator Kerry, who supported [McCain-Feingold], is now the beneficiary of the single largest conspiracy to violate campaign finance laws in history," declared Jill Holtzman Vogel, RNC chief counsel.

The legal challenge collapsed on May 13, when the FEC voted 4 to 2 to put off regulating the 527s until after the Nov. 2 election.

But the ruling ended up allaying the fears of many pro-Republican corporate leaders that they would be risking FEC or court sanctions if they donated to 527 groups.

For PFA, the floodgates were open. Among the early big givers were Carl H. Lindner Jr. and A. Jerrold Perenchio, both Bush campaign "Rangers." They were quickly followed by such other Bush fundraisers as Alexander G. Spanos ($5 million); Dawn Arnall ($5 million); Pickens ($2.5 million); and Alice Walton ($1.6 million).

The FEC decision "put us in the ballgame," McCabe said, "and we've been going full throttle since then."

Not only have the two pro-Republican 527s, PFA and the Swift Boat Veterans, recently outraised the Democrats, but the ads run by PFA and the Swift Boat Veterans have also gained far more notoriety than any of the Democratic 527 ads.

The best-known ad was run in early August, right after the Democratic National Convention, by the Swift Boat Veterans. It attacked Kerry's record in Vietnam, charging, "Kerry is lying about his first Purple Heart" and "Kerry lied to get his Bronze Star." These claims were never substantiated, and they were disputed by the Kerry campaign and in newspaper articles, but questions about Kerry's service dominated the campaign through much of August.

More recently, PFA has produced two harshly anti-Kerry ads that have become subjects of controversy and debate, especially in the battleground states of Wisconsin and Iowa where they are running frequently.

First, on Sept. 22, PFA and the Bush-Cheney campaign put up similar ads showing Kerry tacking while windsurfing and quoting Kerry taking seemingly opposite stands on various issues. The Bush ad concludes, "John Kerry. Whichever way the wind blows." The PFA ad ended with, "Whichever way the wind blows, Kerry rides the wave. And Kerry surfs every direction on Iraq."

More recently, the Bush campaign and the PFA have launched new ad buys with other similar themes. The PFA ad shows pictures of terrorist attacks and such terrorist leaders as Osama bin Laden and Mohamed Atta, as the announcer declares: "These people want to kill us. . . . Would you trust Kerry against these fanatic killers? President Bush didn't start this war, but he will finish it." The Bush campaign ad concludes: "How can John Kerry protect us, when he doesn't even know where he stands?"

The effectiveness of the $1.6 million PFA ad buys was reflected in the fact that the Kerry campaign and the Democratic National Committee were forced to respond with their own ads to defuse the attack.

Asked why the pro-GOP ads have had more impact than the pro-Democratic ads, Bill Galston, a Democratic public policy strategist, said he believes the Republicans have developed "messages that inherently have more leverage than others because they go at something that is at the heart of the campaign" -- in this case Kerry's use of his military record.

"They [the Swift Boat Veterans and PFA] weren't going for a capillary, they were going for the jugular of the Kerry campaign," Galston said.

Researcher Alice Crites contributed to this report.

Tony Feather, force behind 527 PFA.A Swift Boat Veterans commercial, one of the 527 group's efforts to punch holes in John Kerry's Vietnam War record.