BY JIM SPENCER

WASHINGTON – Some members of the U.S. Senate, including Minnesota Democrats Al Franken and Amy Klobuchar, had hoped to vote Monday to shine a light on contributors to groups financing the tens of millions of dollars worth of political attack ads already filling the airwaves in the 2012 presidential election and other races.

Instead, they didn't even get a chance to formally debate the so-called DISCLOSE Act.

Voting as a block, Republicans denied the 60 votes needed to discuss the bill, much less approve or defeat it. The parliamentary maneuver provided another example of the Senate's sometimes bitter political divide.

"If they won't even let us talk about it," Klobuchar said of Republicans, "they're blocking it with a filibuster."

Franken, who along with Klobuchar co-sponsored the legislation, said the failure to act will allow deceptive advertisements to continue to crowd out legitimate debate.

"People should be held accountable for this vote," Franken said. "It's not just a procedural vote. It's a vote against this bill.

"I think Americans must be scratching their heads and saying: 'What is wrong with disclosure?' … This is the simplest, most modest thing we can do: [Let] sunlight be the best disinfectant. Disclose, disclose, disclose."

The DISCLOSE Act would have forced corporations, non-profit groups, labor unions and certain other groups to reveal political donations if they collectively total more than $10,000 in an election reporting cycle.

The legislation came as a response to the unlimited political spending allowed by the Supreme Court's 2010 Citizens United decision. That case authorized unlimited political spending by corporations and labor unions. In response to the decision, independent expenditure groups formed and are now spending hundreds of millions of dollars on negative ads without having to say where the money came from.

"People are running these ads and people have a right to know who's paying for them. That is a cornerstone of our democracy," Klobuchar said.

But she admitted that because of Monday's vote, any fix will almost certainly not take place before the November election.

Franken agreed.

People in Minnesota and around the country "are relying on these ads and they don't even know who they're from," he said. "They don't know what the interest of the people that are bringing this to them is. I think it's very corrosive to our democracy. "