Chip Somodevilla via Getty Images Sen. Bernie Sanders (I-Vt.) backed marriage equality years before Hillary Clinton did, but he wasn't exactly leading the charge on the issue.

WASHINGTON -- Democratic presidential candidate Bernie Sanders has a case of sour grapes over the decision by the Human Rights Campaign, the nation's largest LGBT rights group, to endorse his opponent, Hillary Clinton. He says he doesn't need their stinking support, and he's got a strong record on gay rights anyway. He does.

But his spokesman Michael Briggs made the case Tuesday that Sanders has been way ahead of Clinton -- and pretty much everyone -- in advocating same-sex marriage. He pointed to the senator's support for civil unions in his home state of Vermont back in 2000. Those gave couples some of the same legal protections as marriage, but they didn't provide federal benefits and weren't recognized by other states.

Sanders was "a pioneer on this early version of gay marriage and has by far the most exemplary record on gay rights of any candidate ever in American history," Briggs said in an interview with The Washington Blade.

That's not quite right.

Sanders did support civil unions as far back as 15 years ago, but it was for the same reason he opposed the federal Defense of Marriage Act in 1996: his strong belief in state's rights. He wasn't advocating for legal marriage for same-sex couples. He actually avoided the subject.

As one Vermont columnist put it in 2000, getting a straight answer from Sanders on gay marriage "was like pulling teeth... from a rhinoceros." In 2006, Sanders said he supported civil unions but not same-sex marriage, again deferring to states.

To be sure, if this is a contest between who came around on marriage equality first, Sanders wins. He backed it four years before Clinton did in 2013. And she's hit bumps along the way, between struggling to call DOMA a mistake (her husband signed it into law, so that's awkward) and her uncomfortable interview in 2014 with NPR's Terry Gross, where she dodged questions about her evolution on the issue. She did, however, do a number of things to help LGBT people during her time as secretary of state.

It's been a whole lot easier for Democrats to embrace marriage equality since the Supreme Court struck down DOMA last summer. But if anybody's been a pioneer on this front, it's not Sanders or Clinton. It's someone more like Rep. Jerrold Nadler (D-N.Y.), who has introduced a bill in every Congress since 2009 to repeal DOMA and ticked off right-wing interest groups along the way.