This article is from the archive of our partner National Journal

In the 2014 elections, both sides had enough big money to go around. And while all that spending (and the thousands and thousands of TV ads it bought) is in the past now, the donors who fueled this year's unprecedented deluge of political cash will be back in future elections.

The indispensable Center for Responsive Politics has tracked the biggest individual donors in federal elections over the past two years, and we've added to it by reviewing additional numbers from this year's final Federal Election Commission reports. The list includes some well-known names in political circles, and others that have flown further under the radar. Unfortunately, the list doesn't include donors to political nonprofit organizations (such as Americans for Prosperity or others in the Koch brothers' network), since those groups don't have to report their donors. But here are the biggest super PAC donors we saw in the last election.

1. Tom Steyer

Environmentalist and former hedge-fund manager Tom Steyer made headlines earlier this year with a bold promise to raise and spend over $100 million in 2014, split half-and-half between himself and other donors eager to make the environment a potent political issue this year. But Steyer ended up falling short of his goal—and shouldering most of the load himself. He put $71.9 million of his own money into his NextGen Climate Action Committee, which adds up to well over 90 percent of the $77 million the group had to work with.

In addition to spending directly on Senate races in Colorado, Iowa, Michigan, and New Hampshire, plus a few gubernatorial races, Steyer also funded some other Democratic groups through NextGen. The super PAC distributed millions to Senate Majority PAC, Democrats' main Senate super PAC, as well as to the League of Conservation Voters, another major environmental group.

2. Michael Bloomberg

Not only did former New York City Mayor Bloomberg, an independent, spend more than almost anyone on the midterms, he did it in a unique way true to the "I" after his name. Bloomberg funded his own Independence USA PAC with more than $17 million and used it to back both Democrats and Republicans across the country, including one each in Illinois congressional races. As a bipartisan megadonor, he's almost unique.

Plenty of other groups also benefited from Bloomberg's largesse, and Democratic ones were the biggest beneficiaries. Bloomberg gave $2.75 million to EMILY's List's super PAC, more than $2 million to Democrats' House Majority PAC, and $1 million to Planned Parenthood's super PAC, plus a quarter-million dollars to former Rep. Gabrielle Giffords's gun-control-focused group, Americans for Responsible Solutions PAC. Bloomberg also chipped in a half-million dollars to groups that supported Republicans Sens. Thad Cochran and Lindsey Graham in their primaries.

3. Paul Singer

Hedge-fund manager Paul Singer was a top donor to conservative groups this cycle, spreading contributions of $2 million to $3 million among several different groups, including American Unity PAC, which backed pro-gay marriage Republicans; American Crossroads, the biggest Republican super PAC; and Ending Spending, a super PAC run by another big-donating family, the Rickettses. (More on them soon.)

One House race in particular bore Singer's mark this year. When Rep.-elect Elise Stefanik won her primary in upstate New York, she did it with direct fundraising aid from Singer as well as helpful ads from Crossroads and another super PAC that got major funding from him.

4. Robert Mercer

Mercer, the co-head of hedge fund Renaissance Technologies, was another influential giver to GOP causes (including some that don't always play nice with the rest of the party) during these midterms. The investor gave a half-million dollars to tea-party-aligned groups such as Senate Conservatives Action and more than $1 million to the Club for Growth, another group that's not shy about spending in GOP primaries.

Mercer also gave Freedom Partners Action Fund, a new super PAC affiliated with the Koch brothers, $2.5 million, and he gave another $1.8 million to Ending Spending. Another $1 million contribution went to a super PAC run by former United Nations Ambassador John Bolton.

5. Fred Eychaner

The reclusive media mogul was a top Democratic super PAC donor last election, and 2014 was no different. Eychaner gave $8 million total to House Majority PAC and Senate Majority PAC, Democrats' congressional super PACs that target competitive races around the country. The Chicago-based head of Newsweb also spent a little closer to home, including a super PAC that spent against the Republican in Democratic Sen. Dick Durbin's sleepy reelection race in Illinois.

6. Joe and Marlene Ricketts

Joe Ricketts, the founder of TD Ameritrade, and his wife, Marlene, were the major source of revenue for Ending Spending, the super PAC Ricketts chairs. The two of them donated more than $7.8 million to their group. They also gave much smaller amounts to candidates and groups across the country, including $1,000 to their home-state Republican Party in Nebraska—where their son Pete Ricketts won the gubernatorial election this year.

7. Richard and Elizabeth Uihlein

Uline CEO Richard Uihlein and his wife Elizabeth's fundraising disclosures read like a who's who of conservative outside groups: the Club for Growth, the Madison Action Fund, Ending Spending, Senate Conservatives Action, and more. The groups all received hundreds of thousands of dollars, but most of the couple's money went in smaller amounts to a host of Senate and House candidates and state parties as well as the Republican National Committee.

8. Sheldon and Miriam Adelson

The casino-owning Adelsons made more news in 2012 with their involvement in the presidential race, but they did jump in during October with a $5 million donation to the Congressional Leadership Fund, as well as support for the Republican Jewish Coalition and a handful of House and Senate candidates. Adelson also demonstrates, though, why super PAC donations can be deceiving: He reportedly also donated tens of millions of dollars to GOP-aligned nonprofits in 2014—but they don't have to report their donors.

9. George Soros

One of Republicans' favorite bogeymen, Soros gave half a million dollars each to a number of Democratic groups in 2014, including the opposition research group American Bridge (the group behind the new media guide to Republicans pondering 2016 presidential runs), House Majority PAC, Senate Majority PAC, the League of Conservation Voters, and Planned Parenthood's super PAC.

Honorable Mention: Charles and David Koch

The co-heads of Koch Industries ranked No. 22 and 23 in the Center for Responsive Politics's list of biggest super PAC donors of the cycle. But their involvement in nonprofit groups like Americans for Prosperity and Freedom Partners, two parts of the vast conservative financial network they help run, means their contributions this cycle far outstrip the $2 million each recorded by the Federal Election Commission.

This article is from the archive of our partner National Journal.

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