On Monday, the Senate will vote – and fail – on a measure to increase transparency in campaign finance. The DISCLOSE Act, which was fashioned in response to the Supreme Court’s Citizens United ruling but which failed to become law by one vote in 2010, would require large organizations spending over $10,000 on any activities that use the name or likeness of a political candidate to file disclosure reports with the federal government, including the names of any large donors. It would also include a “stand by your ad” provision, which would force any ad to have the leading donors to the entity that funded it appear at the end to approve the message. There would also be stronger certification requirements to ensure lack of coordination among candidates and outside entities, and money transferred between organizations would be tracked and disclosed as well. The DISCLOSE Act of 2012 has 28 co-sponsors and will probably garner the support of the entire Democratic caucus.

It’s important to state at the outset that the DISCLOSE Act will not pass. Mitch McConnell, Senate Minority Leader, promised a filibuster the day that the floor action was announced. Republicans will block debate on the motion to proceed to the bill.

There’s one wrinkle here. When the vote fails, around 6pm ET on Monday, a group of Democratic Senators, led by bill sponsor Sheldon Whitehouse, plan to hold the floor deep into the night, in a publicity attempt to raise awareness over the blocking of simple disclosure by the Republicans. The goal is to force a second vote Tuesday, but more than that, it’s to shed a spotlight on runaway spending in elections, and the secret donors who would rather fund that work out of the public eye.

On a conference call yesterday, Senator Whitehouse called the DISCLOSE Act “almost obviously the right thing to do” to at least put a label on the flood of special interest money flowing into political campaigns. While this act would not ban or limit that money – and while previous iterations had to include exemptions for groups like the NRA to get conservative Democrats on board – it would force most donors into the light, and give at least a modicum of information to the voter about who supports what candidates.

Needless to say, hopes are not high that this will mean anything to Republican stalwarts, who once supported disclosure over contribution limits, but who now have turned against it. One such shift comes from John McCain, former co-author of the McCain-Feingold campaign finance reform, who has done something of a triple flip on this issue. McCain, after years of work on reforming campaign finance, voted against the DISCLOSE Act in 2010. Then he supported an amicus brief, co-written with Whitehouse, in support of a Montana Supreme Court ruling that banned corporate contributions on political activities. The Supreme Court struck down the Montana ruling quickly, but the McCain/Whitehouse brief gave some hope that McCain was returning to the fold on campaign finance reform. The brief included this passage:

“We are deeply concerned about the rise of unlimited, anonymous money now flooding our elections,” Whitehouse and McCain said in a joint statement. “This unregulated and unaccountable spending invites corruption into our political process, and undermines our democracy. We urge the Supreme Court to make clear that legislatures can take appropriate actions against corrupting influences in campaigns.”

But now, McCain has announced he will not support the DISCLOSE Act on Monday, claiming that the bill treats unions differently than corporations. “If you look at the bill, there’s nothing in it that treats unions any different than anyone else,” Sen. Whitehouse said on the conference call. “(McCain and I) have the same conversation every time, he says we can’t give unions an unfair advantage, I say John, there’s nothing different in here. Show me where there’s a difference.”

Clearly word has come down from the upper echelons of the GOP that nobody can cross the aisle on disclosure when the current rules have worked so well for Republican electoral politics. The somewhat pathetic spectacle of McCain’s twist back and forth is an example of that. While this isn’t likely to change, the all-nighter on Monday could at least make a case to the public about who is blocking disclosure of the dark money that increasingly rules our politics.