When the Supreme Court decided earlier this year to allow corporations to spend unlimited amounts of money to influence elections, the justices in the majority (save Justice Clarence Thomas) took care to note that “prompt disclosure” of political spending would allow citizens to hold candidates, and their funders, accountable. It’s a nice idea…but things haven’t exactly worked out that way.

Instead, Public Citizen reported last week, in the first election after Citizens United, groups funneling money to political activities have increasingly been hiding where their money comes from.

Only 32 percent of the organizations broadcasting electioneering communications in the 2010 primary season revealed in their filings with the Federal Election Commission (FEC) the identities of donors funding their advertisements, according to Public Citizen’s analysis of FEC filings. In contrast, nearly 50 percent revealed their donors in the 2008 election cycle, and close to 100 percent did so in the 2004 and 2006 cycles. Electioneering communications are campaign ads run shortly before elections that focus on candidates but don’t expressly urge a vote for or against them.

Only 10 percent of Republican groups disclosed their funders, in contrast to 50 percent of Democratic groups.

This shouldn’t come as a surprise. As Target learned the hard way this summer, shareholders, consumers, and voters aren’t particularly keen on large corporations bankrolling political campaigns. Funneling money through secretive groups allows corporate political spenders to have the best of both worlds: they can fund the campaigns of candidates favorable to them, and never have to be held accountable.

An attempt this summer to patch up the loophole that allows corporations to keep their election spending secret ran up against stiff opposition from corporate lobbyists and a unified filibuster from the GOP. President Obama summed up the result in his weekly radio address Saturday:

What is clear is that Congress has a responsibility to act. But the truth is, any law will come too late to prevent the damage that has already been done this election season. That is why, any time you see an attack ad by one of these shadowy groups, you should ask yourself, who is paying for this ad? Is it the health insurance lobby? The oil industry? The credit card companies?

But more than that, you can make sure that the tens of millions of dollars spent on misleading ads do not drown out your voice. Because no matter how many ads they run – no matter how many elections they try to buy – the power to determine the fate of this country doesn’t lie in their hands. It lies in yours. It’s up to all of us to defend that most basic American principle of a government of, by, and for the people. What’s at stake is not just an election. It’s our democracy itself.

This fall, the Senate will have another chance to bring the DISCLOSE Act to a vote. As the New York Times pointed out yesterday, the vote should be a no-brainer for moderate senators like Susan Collins and Olympia Snowe of Maine:

The Citizens United decision, paradoxically, supported greater disclosure of donors, but Senate Republicans have filibustered a bill that would eliminate the secrecy shield. Just one vote is preventing passage. That act is coming back for another Senate vote. The two Republican senators from Maine, Susan Collins and Olympia Snowe, might want to read a recent poll by the Maine Citizens for Clean Elections, which showed that 80 percent of the state’s voters support public disclosure.

In a poll we commissioned in June, 85% of Americans said that corporations already have too much influence over the political process. Voters want information. Will Congress provide it?