Updated: 2:31 p.m.

With its unrestricted super PACs, wealthy mega-donors, secret money and more than $6 billion projected price tag, this election cycle boasts more unfettered campaign spending than any in recent memory.

This sea change comes thanks to the Supreme Court’s Citizens United v. Federal Election Commission ruling, which in early 2010 lifted all limits on independent corporate and union spending. Citizens United got a test run during the 2010 elections. But in this first presidential race since the ruling, political players on both sides of the aisle have exploited their new freedoms to the hilt.

The full picture won’t be clear until all the numbers are tallied, weeks or even months after Election Day. But some trends are already clear. Outside spending by super PACs and politically active nonprofits is surging, sometimes drowning out the political parties. Secret campaign spending has spiked. A small handful of millionaires and billionaires have largely bankrolled these outside groups. And voters are more disgusted than ever. Here’s what sets the first post-Citizens United presidential race apart.

Outside Groups Surge

Outside groups such as unrestricted super PACs and politically active nonprofits spent about $890 million through Oct. 31, according to the Center for Responsive Politics, approaching triple the amount they had spent at the same point in 2008. The CRP projects these outside groups will spend $970 million all told this cycle. In many races, including the presidential contest, outside groups have far outspent the two major political parties, which like the candidates still face strict limits on the size and source of contributions.

Democrats once opposed to super PACs have now embraced them, and all told more than 700 unrestricted super PACs have registered with the Federal Election Commission. Some have questioned the efficacy of super PACs, which pay costly ad rates and must keep candidates at arm’s length. But big-spending outside groups could prove decisive in closely contested House races. And established operations such as the pro-GOP super PAC American Crossroads and its affiliated nonprofit Crossroads GPS will only gain clout over time.

Secrecy Reigns

Campaign spending by groups that do not disclose their donors exceeded $265 million as of Oct. 31, according to the Center for Responsive Politics, more than three times the $74 million that non-disclosing groups spent four years ago.

“Voters are not getting the information the Supreme Court said they would get,” said former FEC Chairman Trevor Potter, president and general counsel of the Campaign Legal Center. “And you have a real potential for corruption here, when the officeholders know where the money comes from, and the spenders know where it comes from, but the public doesn’t.”

Driving the trend are politically active 501(c)(4) tax-exempt groups that need not disclose their donors because they are social welfare groups, but that spend tens of millions on ads targeting candidates. Some are donating large sums to super PACs and engaging in complicated money transfers that obscure their funding sources, according to the CRP.

“The lack of disclosure, and meaningful disclosure, are what set this cycle apart,” CRP Executive Director Sheila Krumholz said.

Meet the Mega Donors

Millionaires and billionaires donating $5 million, $10 million and even $50 million to super PACs have underwritten a disproportionate share of the outside spending in this election. A full 67 percent of all super PAC contributions have come from just 209 donors or groups of related donors giving $500,000 or more, according to an analysis by the Huffington Post.

Topping the list is casino mogul Sheldon Adelson, chairman and CEO of the Las Vegas Sands Corp., who with his wife, Miriam, has given $53.7 million to GOP-friendly super PACs, according to the Center for Public Integrity. Other mega-donors include Contran Corp. owner Harold Simmons, who with his wife has given $26.9 million to pro-Republican super PACs, and Texas real estate developer Bob Perry, whose GOP super PAC donations total $21.5 million. Top Democratic super PAC donors include media and publishing mogul Fred Eychaner, who has given $12 million, according to the CPI.

Voters are Fed Up

Conservatives hail the new era of unlimited campaign spending as a boon to voters and to free speech. Republicans say the new rules have also helped them gain parity with big-spending labor unions.

“Money actually breaks up old monopolies, makes more ideas heard, makes more voices heard,” said Center for Competitive Politics co-founder and Chairman Bradley Smith, another former FEC chairman. He added that outside groups “ought to be participating. There’s no reason why the debate should be limited to what candidates and parties want to talk about.”

But polls suggest that voters are not happy with the new, wide-open rules. In a July Gallup poll, respondents listed “reducing corruption in the federal government” as their No. 2 priority, second only to “creating good jobs.” A more recent survey by Bannon Communications Research for the Corporate Reform Coalition, a progressive umbrella group, found that 84 percent of respondents agreed that “corporate money drowns out the voices of average Americans.”

Money Wars Rage On

Candidates, too, deplore the onslaught of often-anonymous campaign ads from outside groups. Look for lawmakers on both sides of the aisle to propose reforms once Congress returns. But don’t expect much common ground. Republicans will want to lift contributions on candidates and parties, a proposal Democrats will reject out of hand. Democrats will continue pushing disclosure legislation and may add public financing, in the form of matching funds for low-dollar donations, to their wish list.

Still, there will be plenty to stoke the political money wars after Election Day.

“There are going to be folks on both sides of the aisle that have seen super PACs and outside groups transforming the election, and they’re going to want to do something about it,” said Adam Skaggs, senior counsel at the Brennan Center for Justice at New York University’s School of Law.