WASHINGTON (AP) — Donald Trump calls them a "crooked business." Bernie Sanders says they're "corrupt" organizations "buying elections."
But the barrage of insults hasn't stopped the political groups known as super PACs and their donors from showing the two presidential candidates some love — no matter how loudly they may rail against their very existence.
"I'm not going to be deterred just by that alone," said Joshua Grossman, president of Progressive Kick, of Sanders' anti-super PAC message. His liberal super PAC, funded by donors who have written checks as large as $250,000, has endorsed Sanders and is planning to spend money helping to elect him.
Unlike formal campaigns for president, super PACs are allowed by law to accept donations of any size. That fact makes them a juicy political target for populist candidates such as Trump and Sanders.
Yet already, a super PAC allied with a nurses' union that endorsed Sanders over Democratic front-runner Hillary Clinton in August has put more than $600,000 into pro-Sanders digital and print ads in the important early primary states of Iowa, New Hampshire, South Carolina and Nevada.
Billboards put up by the super PAC, National Nurses United for Patient Protection, proclaim: "Politics As Usual Won't Guarantee Healthcare For All. Bernie Will."
The union is only able to spend that kind of money because of the 2010 Supreme Court ruling known as Citizens United, a decision that ultimately led to the creation of super PACs. Sanders has decried it as corrosive to democracy.
That ruling also enabled unions to start spending member dues on political advertising in federal elections. Since that time, the nurses' union has moved $3.4 million in dues into its super PAC, according to records filed with the Federal Election Commission. The group hasn't raised money from anyone else.
"Anti-labor folks might say that these unions are extorting money from their dues-paying members to use on politics, whether those members like it or not," said Paul S. Ryan, senior counsel at the Campaign Legal Center in Washington, which advocates for stricter campaign finance rules.
RoseAnn DeMoro, the union's executive director, said the super PAC has helped other candidates in previous elections and is assisting Sanders' bid because "we've never seen a better messenger" for causes important to the union's members, citing as an example his plan to expand Medicare.
"We are hoping to do as much as we can for him," she said. "The nurses are extremely happy with what we've done with their money. He's a vehicle for our voice. We laugh quietly among ourselves and say, 'Bernie stole our issues.'"
The nurses' early endorsement was seen as a political victory for Sanders, who filmed a five-minute video thanking the group's 185,000 members for their support. Nearly three months later, Sanders and his aides defended the group as "good" big money, drawing a contrast with the wealthy corporate donors he frequently vilifies on the campaign trail.
"They are nurses and they are fighting for the health care of their people," Sanders said in an interview last week on CNN. "They are doing what they think is appropriate. I do not have a super PAC."
Sanders has sought to distinguish himself from Clinton on the issue of big money.
While both say they'd like to limit money in politics by rolling back the Citizens United court ruling, Clinton deployed close aides to a super PAC that aims to at least triple the $80 million it raised to support President Barack Obama's re-election. That group, Priorities USA, already has a half-dozen $1 million contributors.
Sanders has not authorized any similar effort. In fact, in June, Sanders' campaign attorney sent a cease-and-desist letter to a strategist who set up a "pro-Sanders" super PAC going by several names, including Bet on Bernie and Americans Socially United.
Cary Lee Peterson, the man who set up the group, has credit and legal problems in several states, an investigation by the Center for Public Integrity found. A campaign finance report the group filed seven weeks late showed it was $50,000 in debt as of the end of June. The group is continuing to solicit money online.
On the other side of the aisle, Trump accuses his opponents of being controlled by the super PACs backing their bids — even calling some "puppets" of their donors.
But super PACs can't seem to quit Trump. At one point his campaign identified nine that appeared to be raising money in the name of helping him. One, called Patriots for Trump, purchased Iowa and New Hampshire voter contact information as recently as late October, FEC records show.
Trump himself attended a several events for a group called Make America Great Again — his slogan. In October, The Washington Post reported on ties between the leader of Make America Great Again and Trump's own aides.
Soon after, Trump asked the group to shut down, and they appeared to do so. At the same time, his campaign sent cease-and-desist letters to other supposedly pro-Trump super PACs, and he ramped up his anti-super-PAC rhetoric.
Many seem to have stopped raising money. One group, called Let's Trump Politics, remains operational — at least online. It formed in late September, according to the FEC, and hasn't yet had to file any fundraising information.
The group's website includes a headline about how "Republicans support political outsiders" — and a disclaimer that its mission is "in no way a direct relation to Donald Trump or his 2016 presidential campaign."
Associated Press writer Jill Colvin contributed to this report from Newark, New Jersey.
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