In an era when campaign cash can swing elections, the 2014 midterms may boil down, at least in part, to a contest between billionaires.

On the left is Tom Steyer, worth $1.6 billion, an outspoken advocate for climate change legislation.

The hedge-fund-manager-turned-environmentalist is reportedly prepared to spend $50 million of his own money to help elect environmentally-friendly Democrats in seven states in 2014. His Super PAC, NextGen Climate, plans to contribute another $50 million. NextGen has announced it will use climate change as a wedge issue, painting Republicans as "anti-science" and submissive to the interests of Big Oil.

The biggest donors on the right do have ties to oil and gas. They're also worth a lot more money.

Reclusive, passionate, often vilified by their detractors, Charles and David Koch own Koch Industries, an oil and gas conglomerate that rakes in over $100 billion in revenue annually. According to Forbes, their current net worth is $40.6 billion - each.

The Koch brothers have consistently opposed climate change legislation and argued for looser EPA regulations. They've also fought against Obamacare and for a balanced budget. They and the conservative group they helped start, Americans for Prosperity, are reportedly planning a $125 million midterm push of their own.

Here's what we know about 2014's battle of the billionaires:

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What's their net worth?	$81.2 billion	$1.6 billion
How old are they?	Charles: 78 David: 74	56
Where do they live?	Charles: Wichita David: New York City	San Francisco
Where'd they go to school?	Charles: M.I.T. David: M.I.T.	Yale & Stanford
How'd they make their money?	Koch Industries, an oil & gas conglomerate that also manufactures textiles and paper goods	Farallon Capital Management, a global hedge fund
What causes are important?	Opposing climate change legislation Opposing Obamacare Promoting tax reform	Promoting climate change legislation
Which races are important to them?	U.S. Senate, Alaska U.S. Senate, Arkansas U.S. Senate, Colorado U.S. Senate, Iowa U.S. Senate, Louisiana U. S. Senate, Michigan U.S. Senate, Montana U.S. Senate, New Hampshire U.S.. Senate, North Carolina U. S. House, Arizona's 1st Congressional District U.S. House, Arizona's 2nd Congressional District U.S. House, Florida's 2nd Congressional District U.S. House, Florida's 18th Congressional District U.S. House, Michigan's 3rd Congressional District U.S. House, Nevada's 3rd Congressional District U.S. House, New Hampshire 1st Congressional District U.S. House, New Hampshire 2nd Congressional District U.S. House, West Virginia's 3rd Congressional District	Florida Governor Maine Governor Pennsylvania Governor U.S. Senate, Colorado U.S. Senate, Iowa U.S. Senate, Michigan U.S. Senate, New Hampshire
What PACs did they help found?	Americans for Prosperity	NextGen Climate Action
Will they make public appearances?	They rarely do, and they have not signaled they will become more visible during the 2014 election cycle.	Steyer,himself, plans to travel to many of the states above, and it looks as if he's prepared to be the public face of these efforts.