The Bushes and Clintons did not derive political power from wealth. Likewise, their great political power does not bestow upon them great wealth (though they certainly are wealthy, they're not in the same universe of, say, Donald Sterling).
And those with wealth, such as the much discussed Koch brothers? Their influence on policy seems to be near zero. Bill Gates had his company dragged through the mud several times.
GWB's great grandfather was a wealthy industrialist that was business partners with one of the wealthiest people in the country, E.H. Harriman (Director of Union Pacific, Southern Pacific, and Wells Fargo). GWB's grandfather, Prescott, made his fortune as VP and Partner at Brown Brothers Harriman, a bank that eventually would employ Prescott's son George HW Bush, as well as Alan Greenspan and several other senators and cabinet members. BBH spun out a division that was ultimately Drexel Burnham Lambert -- the 5th largest I-Bank in the country until Michael Milken blew it up. HW Bush's maternal grandfather started an investment bank that was eventually sold to Merrill Lynch, and was also a director at Harriman brothers. HW's maternal grandfather was president of McCall's (publisher of Popular Mechanics, Redbook, and McCalls before selling them to Hearst).
George HW Bush's business career started at an oil equipment company, Dresser Industries a subsidiary of BBH, where his father had been Director for 20 years. Dresser formed a spin-out JV with Ingersol-Rand and still operates as Dresser-Rand (Mkt Cap: $4.5B). Dresser Industries would go on to be purchased by Halliburton via a Dick Cheney-negotiated deal for ~$8 billion. Some years later, HW Bush would co-found Zapata Petroleum Corporation (with a recently retired CIA agent) and Zapata Offshore (funded largely by Phillip Graham, the owner of WaPo), which he would lead until 1966. Zapata Petroleum became Pennzoil (worth an estimated $4.2B in 1998). Zapata Offshore would eventually rebrand as Harbinger Group (Mkt Cap: $2.4B).
Zapata has a great history if anyone's in the mood for some conspiracy theories: http://en.wikipedia.org/wiki/Harbinger_Group.
Tl;dr:
* Most of their SEC and disclosure records from the 1960's were accidentally destroyed just after HW Bush was appointed to be VP.
* Zapata owned off-shore rigs that served as bases of operations for anti-Castro missions
* The CIA's official codenames for the three boats used in the Bay of Pigs invasion were was actually 'Barbara', 'Houston', and 'Zapata'.
* Within 24 Hours of JFK's assassination, before he had ever ran for office, HW Bush is mentioned by name in a memo prepared by J. Edgar Hoover.
* Bill Liedtke, co-founder of Zapata Petroleum, and then-current Chairman of Pennzoil, personally flew nearly $1M of money laundered through a Mexican bank, to DC to beat the impending campaign finance disclosure midnight deadline on behalf of Richard Nixon. $89,000 of that money ended up in the bank account of one of the Watergate burglars.
George W. Bush, much like Donald Sterling, owned a Major Sports Franchise, though granted it was with an ownership group that only netted him tens of millions when it was sold. I'll ignore all the earlier failures GWB saw when he was backed by US and Saudi billionaires (William Draper, Lewis Leherman, Salem bin Laden, Khalid bin Mahfouz).
So I guess being scions to a family that's spawned multiple billion dollar businesses with activities in banking, venture capital, machinery, railroads, oil and gas, and airlines and being family friends with billionaies had nothing to do with their political power?
It lists $80MM for Clinton.
If the Koch brothers weren't getting a return on their political contributions, I highly doubt they would continue to do so. After the recession there was a big push for wall st regulation, higher taxes on the 1%, and increases in welfare program funding, and yet nothing meaningful came from it despite popular support. My guess is the Koch brothers consider that a success.
"...it's almost impossible to quantify whether the Koch brothers or Soros dominate this political realm. That said, both the Kochs and Soros have spent incredible riches in this area with no sign of stopping."
http://www.opensecrets.org/news/2010/09/opensecrets-battle--...
In the latter case that's pretty clearly true, at least as to their own wealth (as the Clintons weren't particularly wealthy independently of their political success), in the former case, not so much.
I don't agree that the Koch's influence on policy is near-zero, though nor do I think they have the entire GOP in their pocket as the Democrats like to imagine. They're not stupid, they expect a return on their political investment. I'm guessing they've done OK out of subsidies, if nothing else.
I don't mean to be partisan here, you couold say the same thing about various union groups.