Two political action committees backed by former Bush political advisers Karl Rove and Ed Gillespie—American Crossroads and Crossroads GPS—have raised a combined $32 million so far this year. They raised $14.5 million in the last month alone, nearly doubling their intake from the seven previous months. 527 organizations—tax exempt political action committees—like  American Crossroads can’t work with the Republican National Committee. But they do have broad leeway to use their money to affect the outcomes of the fall midterm elections. As Jake Tapper said, the two groups act in effect as a shadow Republican National Committee.

The Washington Post reports that around 6 times as much money was spent last week in support of Republicans as in support of Democrats. If you think that spending reflects a broad groundswell of support for the Republicans, you’re wrong. As Chris Cillizza reports, the three major Democratic campaign committees actually out-raised their Republican counterparts in August. Most of that Republican money comes from outside political action committees like American Crossroads and Crossroads GPS. And for the most part those groups don't get their money from ordinary Americans. Their money comes from a small handful of the richest men in the world.

Justin Elliott reports that 91% of the money American Crossroads raised in August came from just three billionaires: Trevor Rees-Jones, the founder of Chief Oil and Gas; Robert Rowling, whose holding company owns Gold’s Gym and Omni Hotels; and Jerry Perenchio, the former chairman of Univision. The main advantage of the outside groups like American Crossroads and Crossroads GPS, after all, is that there is no limit to how much donors can give. Small donors can give straight to the political parties themselves.

American Crossroads also got another $400,000 from American Financial Group, a holding company principally owned by billionaire Carl Lindner, Jr.—a donation made possible by the Supreme Court’s decision in Citizens United that no limits can be placed on corporate funding of political advertising. And Jim Kuhnhenn points out that American Crossroads had earlier raised $2 million from Harold Simmons, the Texas billionaire who paid for the commercials linking Barack Obama to Weather Underground founder William Ayres. All that is on top of the money that the billionaire Koch brothers have spent bankrolling the Tea Party and the $1 million Australian billionaire Rupert Murdoch’s News Corp.—which owns Fox—gave to the Republican Governors Association this summer. The Democrats have had their billionaire backers too—like George Soros—but nowhere near as many, and that could make a huge difference in the November elections.

Billionaires are people too—not that I've ever met one—and are as entitled as any of us to express their opinions. There is something strange about the idea that they are under attack, when they pay less taxes now than they have since the Reagan administration and take home a substantially larger share of our national income than ever before. But they have every right to try to get voters to see their points of view. The Tea Party may be quietly financed by the Koch brothers’ wealth, but it wouldn’t amount to much if they weren’t able to attract followers.

Still, it’s not obvious that the right to free speech necessarily entails the right to use the loudest megaphone money can buy. And well-financed advertising can drown out other points of view—even when it's misleading or downright dishonest. It is in any case worth knowing where all the money is coming from. In this case, it is important to understand that the case for cutting taxes for the rich and eliminating corporate regulations is being financed almost entirely by the super-wealthy owners of those corporations.