Democrats denounced it as an assault on democracy and a sop to billionaires when the Supreme Court issued a ruling two years ago that loosened limits on campaign giving.
But Hillary Clinton and Democratic Party leaders are now exploiting the decision, funneling tens of millions of dollars from their wealthiest donors into a handful of presidential swing states.
The flow of money, documented in Federal Election Commission reports, shows Democrats expanding their fundraising advantage in the final phase of the presidential race, defying expectations at the beginning of the campaign that Republicans would dominate the money chase. Clinton and the Democrats are now outpacing Trump and the Republicans on every front, according to FEC records: Clinton's campaign, her party and outside groups supporting her have raised almost twice as much as Trump and his allies.
The influx of cash and the new rules have allowed the national Democratic Party to overcome a cash shortage and provide Democrats in key states like Virginia and North Carolina with money for early voting drives, additional staff and canvassing aimed up and down the ticket.
The Democratic National Committee — in debt and underfinanced a year ago — has poured nearly $30 million into these key states through the beginning of September. The funding was powered by a surge of six-figure contributions raised by Clinton from the likes of James Cameron, the Hollywood director, and George Soros, the retired hedge fund manager, as well as several members of the billionaire Pritzker family.
The Republican National Committee has provided the states with just $11 million, limited by Donald Trump's difficulties in persuading the traditional Republican big-donor base to invest in his campaign.
"In many ways, we are kind of used to the concept of building our own empire," said Matt Borges, the executive director of the Republican Party of Ohio, adding that he did not believe Ohio Republicans would be at a disadvantage come Election Day. "I'll take whatever I can get."
More than two-thirds of the Democrats' cash went to a dozen presidential battlegrounds critical to any Clinton victory. The biggest beneficiaries were Florida, which has taken in close to $3.5 million, and Pennsylvania and Ohio, which have each received more than $2 million.
In each of those states, the funds from the national party have made a difference, erasing deficits in federal contributions against the respective Republican state parties.
The money followed a legal but circuitous route turbocharged by the 2014 ruling in McCutcheon v. Federal Election Commission, which struck down Watergate-era limits on the combined amount one person could donate to all federal candidates and parties in an election cycle.
Like other candidates for federal office this year, Clinton can accept only up to $5,400 from any one donor over the course of her campaign. But after the McCutcheon decision, Clinton established an agreement last year with the Democratic Party under which she asked her wealthiest patrons to write checks in excess of $300,000, more than double the old limit, to the Hillary Victory Fund, an account made up of the national and state parties and the Clinton campaign.
That amount is a lump sum equal to the total contributions each donor is allowed to give to her campaign and the DNC, along with $10,000 to each of the 38 state party organizations now participating in the arrangements.
Because there are no limits on how much money party committees can transfer to one another, most of the state parties have cycled their share back to the DNC. The party then moved the cash into a smaller number of battleground states to prepare for Election Day. The effect is a legal end-run around contribution limits, allowing wealthy donors to give far more than $5,400 to help Clinton where she needs it the most.
"If you're a party leader or a candidate who can attract big enough donors, it means contribution limits are for the little guy," said Ian Vandewalker, a counsel at the Brennan Center for Justice, which favors tighter controls on political money. "The party leaders, the candidates who have a national name, significant amounts of their war chests are built from these big checks," he said.
The Democrats' unexpected advantage comes courtesy of a lawsuit filed in 2012 by the RNC and Shaun McCutcheon, an Alabama businessman.
While both parties have used joint fundraising arrangements for years, the decision issued two years ago in the McCutcheon case made it easier to raise and concentrate even more money from the same small group of wealthy donors.
At the time, the Supreme Court's conservative majority rejected concerns that lifting the limit would make candidates more indebted to the biggest donors. During oral arguments, Justice Samuel A. Alito Jr. dismissed the idea that party leaders or candidates in different states would cooperate by sending their contributions elsewhere as "wild hypotheticals."
Democrats also castigated the court, arguing that it had paved the way for the wealthiest donors to further dominate campaign giving.
"With the rate the Supreme Court is going, there will only be three or four people in the whole country that have to finance our entire political system," Clinton said during an appearance in Oregon the week after the McCutcheon decision.
Clinton was no doubt exaggerating for effect. Still, the actual numbers are striking: Just 250 donors have accounted for about $44 million in contributions to the Hillary Victory Fund during the last year.
Josh Schwerin, a spokesman for the Clinton campaign, said that Clinton continued to support new restrictions on campaign money, but that the only way to achieve them was to elect more Democrats who shared her views.
"Hillary Clinton has fought for campaign finance reform her entire career and, as president, will make it a priority to restore the role of everyday voters in elections," Schwerin said, "but the stakes of this election are too high to unilaterally disarm."
By contrast, the money raised by Trump and the Republicans, while robust, has been driven chiefly by small checks from his grass-roots supporters.
And the Republicans have not been as shrewd at maximizing whatever money Trump's large-dollar fundraisers have contributed. More of the Republican big-donor money is being directed into national party accounts that cannot be spent directly on the election.
And the committee for Trump Victory — the collective account set up to receive big contributions for the state, national and Trump campaigns — had shared virtually no cash with the state parties through June. A Republican spokeswoman declined to explain why.
Only one Republican state organization, the Republican Party of Pennsylvania, had received any cash through August, according to Federal Election Commission records. The amount was $1,050, to reimburse the party for tables and chairs.
In an interview, McCutcheon said he did not mind that his lawsuit was paying more dividends for Democrats this year.
"I think a lot of those Democrats were just publicly saying it was a bad idea, but a lot of them were on board," he said. "I don't care what party wins or loses as long as it's a free speech system."