When it comes to money and politics, sometimes things just aren’t what they seem.

Take political endorsements, for instance. Today we were reviewing all the candidates’ coveted — and much touted — endorsements to add to our new web page listing political endorsements.

Tulsi Gabbard, who’s running for the open seat in Congressional District 2, proudly displays her endorsement by VoteVets.org, which she calls “the voice of America’s 21st century patriots” and “one of our nation’s leading veteran advocacy organizations.” The press release on her website reminds us that Gabbard is a veteran herself, having served two deployments to the Middle East.

Imagine the coincidence then when into our email dropped a news release from the Center for Responsive Politics, the well-regarded campaign finance watchdog group, with its latest investigation into who is really fueling these political action committees. Today’s installment of the series that CRP is calling The Shadow Money Trail is all about VoteVets.org, which it turns out gets much of its money not from veterans but from environmental groups.

“An organization begun six years ago by Iraq war veterans received nearly $4 million from environmental groups in 2010, a year during which it spent $3.2 million running ads that targeted congressional candidates and urged passage of a climate bill,” the story begins.

The Sierra Club, the Natural Resources Defense Council and Al Gore’s Alliance for Climate Protection were among the conservation organizations giving hundreds of thousands of dollars each to the VoteVets Action Fund, an arm of VoteVets.org. It seems the VoteVets Action Fund is a 501(c)(4) organization and thus the category of nonprofit that is not required to disclose its contributors publicly. The CRP was able to figure out some of them through filings by the donors groups themselves with the Internal Revenue Service, according to the story.

“The lack of disclosure by the 501(c)(4) groups makes them much more opaque than super PACs, though both are allowed to accept unlimited sums of money from practically any source,” CRP wrote. “Super PACs, however, must identify their donors.”

OK, so obviously vets would be a politically powerful ally on a climate bill that links dependence on foreign oil to escalating dangers to troops in oil-rich war zones.

And we’re not suggesting Tulsi Gabbard would have or should have ferreted out information that it took a politically savvy investigative team to uncover.

But why is VoteVets hiding it?

Maybe because it’s a political no-brainer that a candidate — or a cause — would rather have a veteran than a tree-hugger on its side.