AMERICAN CONSERVATIVE UNION: PRINCIPLES FOR SALE…. There’s been an ongoing and heated dispute between FedEx and UPS lately, stemming from a labor provision currently being debated on the Hill. In a nutshell, UPS already negotiates union contracts with individual locations, and FedEx may soon be forced to do the same, giving up its one national union contract for its express business.

A fierce fight between the two shipping giants has broken out over this, and American Conservative Union, a major conservative lobbying organization, was, as recently as two weeks ago, on FedEx’s side. The ACU said in a recent letter, “We stand with FedEx in opposition to this legislation.”

But that wouldn’t last. The ACU asked FedEx to pony up a couple million dollars for conservative lobbying expenses. FedEx balked, so two weeks later, the American Conservative Union switched sides, and now backs UPS.

In return for the $2 million, ACU offered a range of services that included: “Producing op-eds and articles written by ACU’s Chairman David Keene and / or other members of the ACU’s board of directors. (Note that Mr. Keene writes a weekly column that appears in The Hill.)”

The conservative group’s remarkable demand — black-and-white proof of the longtime Washington practice known as “pay for play” — was contained in a private letter to FedEx that was provided to POLITICO.

The letter exposes the practice by some political interest groups of taking stands not for reasons of pure principle, as their members and supporters might assume, but also in part because a sponsor is paying big money.

It’s an interesting look at how this process, usually played out behind closed doors, really works. For a price, a company can buy the loyalty of a conservative organization, its lobbying operation, and perhaps even some media attention. In this case, the ACU’s Keene didn’t necessarily offer to use his print column for paid advocacy, but the fact that it was mentioned as part of the pitch to FedEx suggests a certain, shall we say, ethical flexibility.

And if one fails to pay that price, wouldn’t you know it, the conservative organization finds that maybe it doesn’t really agree with your principled position after all.

It’s tempting to think a revelation like this would permanently undermine the ACU’s reputation, but I can’t help but wonder if the D.C. establishment, assuming that “everyone does it,” and this is just “how the game is played,” will tolerate a scandal like this.

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.