Congress will look like a bunch of blowhards who are all talk and no action if it doesn't pass the DISCLOSE Act in time to have an impact on the November election, and the clock is running out.

The bill, expected to be brought before the Senate rules committee Thursday, would have a sweeping effect on the congressional and presidential elections. It requires any group seeking to influence an election to disclose its spending and donors within 24 hours of a $10,000-or-more expense or contribution.

The legislation reacts to widespread anger over a pair of ill-conceived Supreme Court rulings that allow corporations, unions, and other special interests to spend unlimited funds on elections, with minimal disclosure.

Already in the current Republican primary, these groups have drowned out candidates' voices and dangerously confused voters. Spending by the so-called super-PACs, as well as their sneakier sisters, known as shadow or independent expenditure groups, has mushroomed.

Shadow groups are the most hazardous of the big-money influence peddlers. Donors, with their identities legally hidden by the tax code, fund political operations and advertising for or against issues. But they also pour unlimited funds into super-PACs, which can run advertising to support or slam specific candidates. Voters don't know who is behind the money, but the candidates do.

So far, these groups have spent $83 million on the Republican primary, according to the Center for Responsive Politics. The four surviving GOP candidates have spent $132 million. That gives the shadow groups extraordinary influence over the eventual nominee.

The groups have artificially extended the Republican presidential primary. Newt Gingrich, for example, has been unable to raise enough money to stay in the race, but the super-PACs supporting him have kept his candidacy on life support for weeks.

Not only does the DISCLOSE Act require more frequent disclosure by super-PACs, but the shadow groups also must unmask their donors if they want to continue telling Americans how to vote. Unfortunately, the Senate bill does not include a House provision that requires companies, unions, and other big spenders to disclose their political activities to shareholders or members.

In a somewhat related effort to fix its reputation, Congress recently passed an ethics bill that prohibits members from insider trading. Appallingly, some members have actually used information obtained in their official capacities to play the stock market.

Unfortunately, however, this bill, too, was watered down. It no longer requires "political intelligence" firms, which may use information gained in congressional proceedings, to disclose their sources. That is a shame, because it gives an unfair advantage to an elite group of investors who have knowledge not available to the general public.

Congress failed to pass another version of the DISCLOSE Act in 2010. But now it has another chance to reduce the influence of big money on politics and governance when it matters most. The DISCLOSE Act may not be perfect, but it's needed so the general election doesn't resemble the Republican primaries, which so far have been defined not by the issues, but by deep-pocketed backers.