Republicans ride avalanche of money into November

And you'll never guess who's behind the money pile-up:

The U.S. Chamber of Commerce, the biggest collection point for corporate contributions, has increased its spending for the congressional election in November from $35 million in 2008 to a projected $75 million this year. Officials say it may go even higher.

The chamber has been joined by new conservative fundraising organizations — such as American Crossroads, affiliated with Republican strategist Karl Rove — that have committed to raising tens of millions of dollars.

Here's a little missive from American Crossroads about its mission:

American Crossroads is a new kind of non-profit political organization dedicated to renewing America’s commitment to individual liberty, limited government, free enterprise and a strong national defense—through informed and effective political action by citizens like you.

And here are those "citizens like you":

And despite the group's description of itself as "grassroots," Salon's review of its IRS filings show that four billionaires have contributed 97 percent of the $4.7 million it has raised to date. There are no limits on how much corporations, unions, and individuals can donate to 527 groups. Here's a guide to American Crossroads' four donors:

•Trevor Rees-Jones, president of Dallas-based Chief Oil and Gas, gave a $1 million donation to American Crossroads just as the group was starting in April. That's small money for Rees-Jones, who, Forbes estimated in 2009, amassed a $1.5 billion fortune investing in gas prospects around America. He has also been a big donor to John McCain and the Texas Republican Party, Politico reported.

• Bradley Wayne Hughes, chairman of Public Storage Inc, is American Crossroads' biggest donor, contributing $1.55 million to date. Hughes founded Public Storage in 1972 and the company has grown into a self-storage behemouth with over 2,000 locations. Worth $3.9 billion, he lives in Lexington, KY, where he actively raises thoroughbred horses at Spendthrift Farm. (Hughes' son, B. Wayne Hughes Jr., is on the board of former Senator Norm Coleman's new conservative group, the American Action Network.)

• A company called Southwest Louisiana Land LLC donated $1 million to American Crossroads in June. It turns out Southwest, which doesn't have much of a public footprint, is owned by Dallas billionaire investor Harold Simmons -- no stranger to conservative causes. Since the 1980s, he has ponied up for everthing from Oliver North's defense fund, to Newt Gingrich's PAC, to the Swift Boat Veterans for Truth in 2004, to the American Issues Project, a group that ran ads attempting to tie Obama to Bill Ayers in 2008 (Simmons was the sole funder of the Ayers effort, giving nearly $3 million.) Simmons is worth $4.5 billion.

• TRT Holdings, owned by Dallas' Robert Rowling, gave American Crossroads $1 million. Rowling, whose firm owns Omni Hotels and Gold's Gym, got started at his father's successful company, Tana Oil & Gas. He's now worth $4.4 billion. In 2004 Rowling gave $1 million to Progress for America, an outside group backing President Bush's reelection.