The campaign started modestly Aug. 16: Raise $50,000 from 1,000 donors to send a message to U.S. Sen. Susan Collins of Maine.

By Aug. 21, the goalpost had moved to $200,000 — then to $500,000 … $1 million … $1.5 million … $2 million and rising. By the time Collins had cast her decisive vote to confirm Supreme Court nominee Brett Kavanaugh on Oct. 6, more than 100,000 donors nationwide had pledged more than $3 million to her as-yet-unknown Democratic opponent in 2020.

The unprecedented campaign, which Collins has labeled a bribe, is a testament to the power of small-dollar “crowdfunding” at a time when — post-Citizens United — corporations, interest groups and wealthy donors can dump unlimited piles of cash into elections. Yet the tactics used by the three organizations behind the campaign to pressure Collins — two of them based in Maine — are raising sticky legal questions that could end up in court, with national implications.

“It’s a violation of criminal law and I believe these people should be prosecuted,” said Cleta Mitchell, a conservative political law attorney who has argued campaign finance cases before the Federal Election Commission and the U.S. Supreme Court.

“I think you’d be pretty hard-pressed to say anything here represents a bribe,” countered Bradley Smith, a former chairman and Republican member of the Federal Election Commission, as well as a staunch defender of the concept that campaign donations are “free speech.”

While crowdfunding for charitable causes or startup business investment has been around for years, political operatives are increasingly adept at utilizing social media’s instant, international messaging to create viral fundraising campaigns. Earlier this year, for instance, the small Lewiston Democratic City Committee tapped into national outrage over gun violence to raise more than $180,000 to defeat a legislative candidate.

The Crowdpac campaign against Collins — organized by the Be A Hero PAC, the Maine People’s Alliance and Mainers for Accountable Leadership — was unique in several ways, starting with the underlying premise.

In an effort to pressure Maine’s senior senator on the Kavanaugh vote, the organizers pledged to only collect the donations and give them to a hypothetical Democratic challenger in 2020 if Collins voted to confirm the nominee. If she opposed Kavanaugh, whose nomination nearly collapsed amid allegations of sexual misconduct, no money would be collected.

“Mainers and other Americans made a very simple statement with this campaign: if Senator Collins wouldn’t stand for their values, they would stand for someone else in 2020,” said TJ Adams-Falconer, a spokesman for Crowdpac, which hosts crowdfunding campaigns for progressive candidates or causes.

“Senator Collins chose to stand with Judge Kavanaugh rather than with the majority of her constituents who did not want him on the Supreme Court. Crowdpac gave these individuals a platform to be heard by organizing and amplifying their voices, which should surely count more than any Super PAC,” he said.

But Collins and others have equated the campaign to a bribe or extortion because it uses money as a way to compel her vote on a specific, singular issue.

“This is a classic quid pro quo as defined in our bribery laws,” Collins told the CBS program “60 Minutes” a day after the Senate confirmed Kavanaugh. “They are asking me to perform an official act and if I do not do what they want, $2 million plus is going to go to my opponent. I think that if our politics has come to the point where people are trying to buy votes and buy positions, then we are in a very sad place.”

There is disagreement, however, over the law’s application to this fundraising campaign.

Federal law states that someone is guilty of bribery of a public official when that person “directly or indirectly, corruptly gives or promises anything of value … or offers or promises … to give anything of value to any person or entity, with intent to influence an official act.”

Courts have ruled that “anything of value” can be tangible or intangible payments and need not go to the public official himself or herself. In the case of campaign contributions, the courts have said a bribe occurs when a payment is made “in return for an explicit promise or undertaking by the official to perform or not to perform an official act,” according to an analysis by Columbia Law School’s Center for the Advancement of Public Integrity.

To Mitchell, the conservative attorney who specializes in campaign finance, lobbying and ethics laws, this is a clear-cut case.

“I believe very strongly in the right of people to contribute money to support the candidate of their choice, but this is different,” said Mitchell, a partner at the Washington, D.C.-based law firm Foley & Lardner. “I don’t believe – and the law does not allow – money to be connected to a certain action.”

But defenders say the Collins-pressure campaign was no different than, say, the National Rifle Association or the AFL-CIO making clear they will campaign against elected officials who do not vote their way on particular issues.

“This is a clear-cut case of false outrage,” said Columbia Law School professor Richard Briffault, co-author of several books on campaign finance reform. Not only is there “nothing to be outraged about,” the campaign is consistent with Republicans’ philosophy of money as “free speech” in numerous cases, including the Supreme Court’s 2010 Citizens United case, he said.

In Citizens United, which was decided on a 5-4 vote, the court ruled the federal government cannot place restrictions on how much corporations and labor unions spend on political or election messaging. A subsequent federal court decision, building off Citizens United, struck down limits on how much groups or individuals can contribute to independent, outside organizations. As a result, billionaires on both sides of the aisle can now donate huge sums to so-called “super PACs” that fill the airwaves with campaign advertisements, many of them negative.

Briffault pointed out that Collins would not receive any money whether she voted for or against Kavanaugh. While he acknowledged the Crowdpac campaign’s pre-emptive strategy was unusual, he doesn’t believe it ran afoul of the bribery statute.

“I will acknowledge that something like this hasn’t happened before or at least not at this (scale), Briffault said. “That said, I do not think it is very different than the views of any large organization that says, ‘Our support for a certain candidate will depend on his or her vote’ on tax cuts, abortion, health care or any other issue.”

Likewise, former Federal Election Commission chairman Bradley Smith compares the threat of funding Collins’ would-be opponent in 2020 to a group pledging to turn out throngs of voters to oppose a candidate because of a certain vote.

Neither meets the definition of “corrupt intent” required for something to be a bribe in Smith’s eyes. That doesn’t preclude “a really ambitious prosecutor” from trying – and potentially succeeding – to convince a grand jury to at least indict on the charge, he said. But Smith, who served on the FEC from 2000 to 2005, believes Crowdpac could be vulnerable to other complaints.

Specifically, Crowdpac received an advisory opinion from the FEC affirming its fundraising tactics at a time when it pledged to offer its crowdfunding services to candidates of any party. But the organization has since decided to only serve Democratic or progressive candidates.

“I expect that the FEC would probably not generate the votes to investigate this … and may say, ‘We have more important things to do,’” said Smith, a professor at Capital University Law School in Ohio and chairman of the Institute for Free Speech.

“Some of it may depend on whether it is successful. … I suspect that the tactic is just not going to work very well. If Susan Collins runs for reelection, she is going to say she didn’t cave and that she voted based on what she thought was right.”

At least one organization is already pushing for a federal inquiry into the Crowdpac campaign.

In a Sept. 13 letter to the U.S. Department of Justice, the Foundation for Accountability and Civic Trust wrote that Be A Hero, the Maine People’s Alliance and Mainers for Accountable Leadership “have explicitly explained” that their fundraising campaign was aimed at influencing Collins on a single vote.

“It does not matter that the payment is given to another or that it is in the form of political contributions,” the letter states. “The law specifically includes payments to another as bribery, as well as political contributions, so long as the payment is an attempt to influence an official act. In fact, the groups acknowledge the power of their bribe to influence – (saying) it is ‘a stronger message than a phone call or tweet.’”

The foundation did not return a call seeking comment, and it was unclear whether the letter sparked any movement within the Justice Department.

Collins’ spokeswoman, Annie Clark, said that “threats and other attempts to bully her did not factor into her decision-making whatsoever” on Kavanaugh.

“Bribery does not work on Senator Collins,” Clark said in a statement. “Extortion does not work on Senator Collins. And anybody who thinks these tactics would influence Senator Collins obviously doesn’t know her.”

Clark did not respond to a request for comment on whether Collins would challenge the fundraising in court or with the FEC. Mitchell, the Washington finance attorney, said anyone would have standing to file a complaint with the FEC.

Adams-Falconer, the Crowdpac spokesman, noted that his organization opposes the Citizens United decision that has given money an even bigger role in politics. But he said Crowdpac’s methods are well “within the bounds of campaign finance law.”

“Up until now, only corporations and the super-rich could afford to use this type of speech, pouring millions in dark money into elections,” Adams-Falconer said. “Crowdpac has changed this, bringing this new and powerful form of political speech to everyday citizens. This isn’t bribery, it’s how our campaign finance system currently works.”

Crowdpac collected credit card numbers from those who pledged donations and would charge the accounts only if Collins decides to run in 2020, a decision she hasn’t yet publicly announced.

Marie Follayttar, a co-founder of Mainers for Accountable Leadership, said her organization engaged in multiple ways to convey supporters’ feeling on Kavanaugh to Collins, from letters and phone calls to visits to her offices in Maine and Washington, D.C. They opted to join the Be A Hero campaign on Crowdpac because, unlike the immediate enthusiasm around a rally, the campaign contributions will last until 2020.

But while Follayttar said it was thrilling to see the pledged donations pour in, she added “the whole ask was bittersweet because we didn’t want to have to a war chest” for an opponent.

“I think this will change how we discuss political change and how we advocate,” Follayttar said. “But this next candidate has a chance to not accept any corporate PAC money, and that’s about as ‘Clean Elections’ as you can possibly get.”

Sen. Susan Collins, R-Maine, right, talks with a reporter on Capitol Hill on Oct. 10 in Washington. (AP Photo/Alex Brandon)

Protesters sit and chant Sept. 24 in opposition to Judge Brett Kavanaugh as Capitol Hill Police officers make arrests outside the office of U.S. Sen. Susan Collins, R-Maine, on Capitol Hill in Washington. (Alex Brandon/AP file photo)