While GOP congressional leaders have made clear they’d like to extend the payroll tax break for another year, several prominent Republicans have begun crafting an excuse for failure. The new line: they have to let the tax cut lapse because they just love Social Security too much.

Let’s take a step back and provide some policy context here. The payroll tax that American workers pay goes into the Social Security system to pay benefits for retirees. What happens if the payroll tax is cut? In this case, nothing — proponents replace the lost revenue with money from the general fund. Workers find some additional money in every paycheck, and integrity of the Social Security finances isn’t affected. No muss, no fuss.

You don’t have to take my word for it — Social Security’s chief actuary told policymakers yesterday the system “would be unaffected by enactment of this” tax cut.

But for Republicans who don’t want to give the middle class a tax break, these details are proving inconvenient, and as such, they’re being ignored. Here’s Sen. Jim DeMint (R-S.C.) on CNBC this week:

“Republicans are always ready to cut taxes, as you know. We don’t think it’s a good idea to do it by raiding Social Security.”

And here’s Sen. Rand Paul (R-Ky.) on Fox News:

“[T]he president is advocating reducing the amount of funding to Social Security when they’re already $6 trillion short. So it doesn’t really make any sense and it really argues that he’s going to bankrupt Social Security even quicker by reducing its funding.”

And here’s Sen. Ron Johnson (R-Wis.) to Dave Weigel:

“The payroll tax is targeted toward making Social Security stable. I don’t want to harm the stability of our Social Security system.”

Rush Limbaugh and the House Republican leadership have gotten in on the same game.

It’s quite a transition, isn’t it? Not quite three months ago, all kinds of leading GOP voices were comfortable condemning Social Security as a “Ponzi scheme.” This week, Republicans are prepared to stick the middle class with a tax hike because of their deep and abiding love for this “Ponzi scheme.”

Indeed, the irony of the rhetoric from DeMint, Paul, and Johnson is especially rich. These are three pretty extreme right-wing ideologues, who, when pushed, admit they’d love to privatize Social Security out of existence. It makes this new rhetoric rather amusing, for lack of a better word.

For the record, they’re entirely wrong. If the payroll break is extended, Social Security wouldn’t be “raided”; it wouldn’t “bankrupted”; and it wouldn’t be “harmed.” The system wouldn’t lose so much as a dime. Either Republicans don’t understand the basics of this policy debate, or they do, and they’re playing the public for fools.

Either way, Washington’s biggest foes of Social Security are doing their very best to pretend they’re Social Security’s biggest champions. It’s a shameless, inane con.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.