They set up a super PAC and began sending out brochures, eventually attracting thousands who signed up and gave money.
When Carson actually got around to running, his campaign used those names to jump-start his early fundraising, according to John Philip Sousa IV, great-grandson of the composer and chairman of the 2016 Committee, a super PAC backing Carson.
"It was that list that launched his campaign," Sousa said, saying those names helped Carson build his $20 million in contributions.
The power of super PACs was unleashed by a series of Supreme Court decisions dating to 1976, including Citizens United in 2010, that opened the door to unlimited contributions to political groups — so long as they didn't coordinate with campaigns.
This presidential cycle, that rule is being stretched like never before, as super PACs shadow candidates and take on roles once reserved for the campaign organizations themselves — even staging campaign rallies.
Many of the super PACs and the campaigns are run by a revolving door of close friends and staffers, ensuring that the two sides share a common playbook even when they avoid tripping over the vague
One Democratic commissioner at the FEC said that she is "very concerned" about the growing influence of super PACs and frustrated about the inability of her agency to do anything about it.
"These super PACS are more and more operating as arms of the campaigns," said Ellen Weintraub, a former campaign finance lawyer. "I just find it hard to reconcile the notion that there's no potential for corruption with super PACs raising and spending unlimited amounts of money."
She said it was not surprising that campaigns and their allies were pushing the boundaries because the three Republican commissioners had blocked any attempt to write rules to limit super PACs.
"Our inaction is feeding a culture out there that says political actors don't really have to abide by the rules, because if they don't, nothing is going to happen," she said.
The top Republican on the FEC, vice chairman Matthew Petersen, did not respond to a request for comment.
So far in the 2016 presidential cycle, super PACs have been particularly dominant among Republicans, as outside groups have raised a total of $236.5 million, dwarfing the $64.1 million in campaign accounts though June 15. For Democrats, candidates have raised nearly $50 million while the super PACs totaled $20.5 million.
Early this year,
Bush was routinely seen in front of "Right to Rise" banners and he sometimes stumbled when asked about his plans — saying he was running and then immediately taking it back.
Much of the basic political grunt work for Carly Fiorina's campaign is being handled by a super PAC, Carly for America, which sends staff and volunteers to shadow her on the campaign trail, setting up tables, taking down voters' names and handing out buttons and bumper stickers.
The 2016 Committee backing Carson has paid staff in four states and volunteers that show up at his events and hand out copies of Sousa's 212-page paperback, "Rx for America," that describes the retired neurologist as "the one man who can save the America that our Founding Fathers created." The group has raised about $3.8 million and has built a field organization that hangs brochures on doorknobs and proselytizes for Carson at churches and county fairs.
Groups supporting Hillary Rodham Clinton are part of this phenomenon too. A rapid-response group called Correct the Record broke away from a pro-Hillary super PAC and is now working directly with the campaign. A spokeswoman for the group contends an FEC loophole means that the coordination regulation doesn't apply to them because their work is posted only online.
Richard L. Hasen, an expert on campaign finance at UC Irvine, said candidates were poking holes in the argument that there is no problem in unlimited donations to outside groups.
"The whole conceit of a super PAC is that it is supposed to be independent of a candidate and does not present the potential for corruption," he said. "The close relationship between super PACs and candidates this time really puts that to the test."
At the same time, the early crashes of the campaigns of Rick Perry and
"There were things we couldn't do. We could do a whole bunch — pay for media, the ground game, but we couldn't pay for candidate travel" or fees to get on primary ballots, said Austin Barbour, who served as chief strategist for super PACs supporting Perry.
"I think people are finding out the hard way that campaigns still matter," said Peter Pasi, a GOP digital consultant based in Washington. "You still need to keep the lights on; you still need to pay people."
He believes that some campaigns are leaning too much on super PAC dollars and neglecting the work required to build a base of small-donor supporters – and will suffer for it.
"It's important to remember the old stuff that still works," Pasi said.
Many of the outside groups are run by old allies who intimately know their candidate's thinking. Right to Rise, for example, is led by Mike Murphy, a GOP strategist who has been running Jeb Bush's campaigns since 1998.
"He's a good friend and I'm going to miss him," Bush said two days before he entered the race.
Staff frequently move back and forth. Terry Giles, a Houston lawyer, served as Carson's original campaign chairman. He resigned in June, soon after Carson formally entered the race, so he could begin advising the super PACs — after a 120-day cooling-off period required by the FEC.
"I'll be getting them in alignment with the message that I know Ben wants," said Giles, who plans to meet with Sousa and leaders of two other pro-Carson super PACs. "There needs to be coordination on how the money is spent, to make sure it's spent as efficiently as it can be."
After that task is done, Giles said, he will return to a role as Carson advisor and debate coach, though without any position in the campaign. He said his plan to move back and forth complies with election laws.
He's not alone: Carly for America political director Tom Szold over the summer took a similar role in Fiorina's campaign.
The super PAC representatives say it isn't hard to avoid crossing the line on coordination. For instance, staff members at Carly for America say they track Fiorina's movements by checking the candidate's schedule, posted online.
"We work hard to get our volunteers there and help the people on the ground," said Katie Hughes, spokeswoman for Carly for America. "We would love to help connect them with other Carly supporters."
Sousa said his group had "bent over backward" to avoid coordinating. Sharing the list of supporters is no problem because the super PAC charged the Carson campaign a fair rate, he said.
"It's frustrating at times," Sousa said. "If I speak, three people show up. If Dr. Carson shows up at an event, we could have 3,000 or 30,000, but we don't dare invite him."
Some advocates are pushing for the FEC to draw clearer lines on what super PACs can and can't do. In March, two groups that want stricter limits on political spending filed a complaint against Bush, saying he kept raising money for Right to Rise long after he had decided to run.
"I doubt he was telling people, 'I really, really haven't made up my mind,' and still raised $100 million," said Larry Noble, former FEC general counsel and now a lawyer for the Campaign Legal Center, one of the groups filing the complaint. But even Noble says it's unlikely the FEC will take up the complaint before the election.
"Hope springs eternal," he said. "But given everything we've seen in recent years, I seriously doubt it."
Staff writer Maloy Moore contributed to this report.
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