The “shadow” Democratic Party — the tight universe of well-heeled, lightly regulated entities that are registering and mobilizing voters nationwide — may not be in the forefront in Boston this week. But they’re hardly hiding out in the shadows.

From rallies with Democratic also-ran Howard Dean and “Fahrenheit 9/11” filmmaker Michael Moore to private meetings with high-dollar donors, such groups as the Campaign for America’s Future and the Media Fund are out in full force in Boston — while taking precautions to avoid being charged with illegally coordinating their activities with the official Kerry-Edwards campaign and the Democratic National Committee.

“In 2000, we saw the ‘shadow’ conventions that protested the convention. This is more about progressives coming together to move America forward,” said Toby Chaudhuri of the Campaign for America’s Future.

Indeed, unlike the intraparty rifts created by the shadow conventions four years ago, most of the liberal-leaning groups in Boston are either implicitly or explicitly supporting Democratic presidential candidate Sen. John Kerry (Mass.).

And officials with the “real” Democratic Party aren’t complaining.

“The more people they involve, the more people they can register to vote, the more excitement they can get to get people fired up at the grassroots,” said Democratic Party Chairman Terry McAuliffe. “Let them keep going. They’re not a distraction at all. They’re … helping us show America what a horrible administration the Bush-Cheney administration is for America.”

In fact, so-called “527” political groups — which can accept unlimited donations from businesses, labor unions and individuals — have enabled Democrats to match and even surpass President Bush’s campaign-advertising budget for the key battleground states, said Erik Smith, president of The Media Fund.

While the Bush campaign has spent more than $86 million on political advertising so far, the official Kerry campaign has spent a little more than $73 million. But when the calculations include the $42.4 million spent on political ads by pro-Democratic 527s, the total Democratic message has outpaced that of the Republicans by $32 million, Smith said.

Along with Campaign for America’s Future and The Media Fund, nearly every major liberal-leaning 527 political group — so named for the section of the tax code under which they are regulated — is in Boston, hoping to promote its agenda and raise even more than the hundreds of millions of dollars in unlimited soft-money donations they’ve already raked in during the 2004 campaign cycle.

The mother of all 527s — America Coming Together, headed by Democratic Party heavyweights Ellen Malcolm, Harold Ickes and Steve Rosenthal — has declared its presence openly, even brazenly.

On Saturday night, as thousands of reporters and media executives in taxis and buses streamed toward the Boston Convention and Exhibition Center for the media welcoming party, dozens of volunteers wearing ACT T-shirts held up 6-foot-tall cardboard letters that spelled out such motivational messages as “VICTORY” and “ACT.”

But strategists say the important work is being done behind the scenes.

“We’re meeting with our donors in small, private conversations,” said Sarah Leonard, spokeswoman for ACT. Leonard noted that ACT is “taking advantage of the proximity” of both established and potentially new donors.

In fact, ACT’s fundraising success recently prompted Malcolm to raise the budget for ACT’s voter-registration and education activities from $95 million to $125 million, Malcolm said Monday.

But sensitivities over whether the Kerry campaign and ACT — or other 527s — have coordinated their activities are persistent.

For example, McAuliffe was careful to note that the DNC has “no coordination whatsoever” with ACT or any other Democratic-leaning 527 group.

And Malcolm noted several times in a press conference Monday that ACT is abiding by strict new campaign finance laws that prohibit parties from coordinating activities with groups that accept soft money.

“We are confident that ACT as a political action committee is completely complying with election law,” she said. “We’re raising hard money and unlimited amounts of soft money to get the job done.”

When pressed by reporters, Malcolm defended her group’s decision to come to Boston, noting that many other political groups that support Democratic candidates have also converged on the city — including NARAL Pro-Choice America, the League of Conservation Voters and gun-control advocates.

“All kinds of organizations are here,” said Malcolm. “The confusion is that this is something new that we concocted in the backroom. Political action committees have been active since the 1970s.”

But Chaudhuri, of the Campaign for America’s Future, said that even if coordination weren’t illegal, many of the left-wing 527s wouldn’t want to coordinate with a national candidate, who inevitably would have more rigid campaign structures. They prefer to be outside the party structure, he said.

ACT and the Campaign for America’s Future are also part of a coalition of 33 groups that have joined together under the title “America Votes.” The group boasts in a press release that the combined force of its members represents an “investment of more than $250 million” into voter registration and education.

America Votes is sponsoring a number of media events throughout the week, mostly to tout their own successes at raising money and registering voters for the election. Some briefings also showcase recent polls the groups have commissioned to bolster their view that the issues they care about are also the issues average Americans care about.

But not everyone has come to Boston. The leaders of MoveOn.org, which has spent more than $6 million so far on ads critical of Bush, declined to visit. However, MoveOn.org has allowed its name to be used as co-sponsors of many events in Boston.

Meanwhile, Chaudhuri said many of the pro-Democratic groups are using the Democratic convention as a platform to build a movement of progressives that lasts long past Nov. 2, 2004.

“It’s more than just winning back the White House, it’s about building a movement to change America,” he said.

Louis Jacobson contributed to this report.