Meet 2014's Top Mega-Donors

These Americans have spent millions this midterm.

— -- intro: The overwhelming number of Americans who will vote in the mid-term elections on Nov. 5 won't have contributed a penny to their candidates' campaigns.

But a handful of people will have given more. A lot more.

More than a quarter of the $6 billion contributed to campaigns in 2012 came from about 31,500 individual donors, according to the Sunlight Foundation, which found that not a single candidate won two years ago without the help of the group dubbed the “one percent of the one percent.”

As politics becomes more expensive with every election cycle, these super donors have never been more important.

Here are the top 10 individual donors of the 2014 election cycle, compiled for ABC News by the Center for Responsive Politics from a study of the most recent publicly available campaign financial disclosure reports.

(This ranking does not take into account unreported donations made to 501(c) 4 nonprofit organizations, which are not required to disclose their donors. According to the Center for Responsive Politics, spending by these “dark money” groups in the midterm elections could hit $1 billion.)

quicklist:1title:Tom and Kathryn Steyer, $42.95 million, Democrat

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text: The former mayor of New York City is still working to shape the national political agenda. His anti-gun group Everytown for Gun Safety has endorsed candidates in 28 states, and is supporting a Washington ballot initiative to expand background checks for firearm purchases. Through his Independence USA PAC, Bloomberg, 72, will also spend $25 million in support of centrists in statewide and national races, including Massachusetts Republican Charlie Baker, who is running for governor, and Democratic Rep. Gary Peters, who is running for Senate in Michigan, according to the New York Times.

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quicklist:3title:Fred Eychaner, $7.84 million, Democrat

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quicklist:6title:Robert and Diana Mercer, $3.71 million, Republican

text: Robert Mercer, a New York hedge fund manager, spent millions in 2012 contributing to GOP establishment groups like American Crossroads. This cycle, he’s also spent big on tea party Republicans. According to disclosure records, Mercer, 67, and his wife Diana have contributed to the Senate campaigns of Chris McDaniel in Mississippi, Greg Brannon in North Carolina, Joni Ernst in Iowa and Rep. David Vitter in Louisiana.

quicklist:7title:James and Marilyn Simons, $3.41 million, Democrat

text: At 23, James Simons had earned his PhD in mathematics. Three years later, he was a code breaker for the National Security Agency. In the half century since, Simons, 76, has made billions revolutionizing investment banking -- Robert Mercer, who appears on this list, runs the firm Simons founded -- and establishing himself as a leading political and philanthropic donor. This cycle, he's given $3 million to Democrats’ House and Senate Super PACs. His wife, an economist, has contributed to Planned Parenthood’s political arm and Ready for Hillary. The couple has also contributed to the campaigns of New York Reps. Steve Israel and Tim Bishop.

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quicklist:8title:John "Joe" and Marlene Ricketts, $3.2 million, Republican

text: John, the billionaire founder of online brokerage TD Ameritrade and head of the family that owns the Chicago Cubs, is best known in political circles for spending millions to defeat and discredit President Obama in 2012, including efforts to design an ad campaign that would have connected Obama to incendiary comments made by former spiritual adviser Rev. Jeremiah Wright, and financing the controversial film “2016: Obama’s America.” This cycle, his wife Marlene has contributed millions to the Ricketts’ Ending Spending Action Fund, and supported the campaigns of Republicans like Michigan Senate candidate Terri Lyn Land, Arizona Congressional candidate Martha McSally and Virginia Congressional candidate Barbara Comstock.

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quicklist:9title:Robert and Doylene Perry, $3.12 million, Republican

text: Robert Perry, the late Houston development magnate and longtime Bush supporter who passed away in April 2013, made headlines for bankrolling Swift Boat Veterans for Truth, the conservative veterans’ organization that discredited John Kerry’s Vietnam War service record during his presidential bid in 2004. In 2013, Perry ‘s wife, Doylene, wrote checks to Senate Conservatives Action and the reelection campaign of Texas Sen. John Cornyn.

quicklist:10title:George Soros, $2.5 million, Democrat

text: Soros, the dean of liberal mega-donors, famously told the Washington Post that defeating President George W. Bush in 2004 was the “central focus of my life,” and backed up his words with $24 million in 2003 and 2004. This cycle, Soros, 84, has given more than $2 million to American Bridge, a Democratic opposition research firm, and Democrats including New York Rep. Tim Bishop, Delaware Sen. Chris Coons, and at-risk Sens. Kay Hagan of North Carolina, Mark Udall of Colorado and Jeanne Shaheen of New Hampshire.media: 26322515