And then there were three.

U.S. Senator Tim Johnson today announced that he has decided to support marriage equality legislation. Johnson’s statement is below.

“After lengthy consideration, my views have evolved sufficiently to support marriage equality legislation. This position doesn’t require any religious denomination to alter any of its tenets; it simply forbids government from discrimination regarding who can marry whom.”

So rote has this sort of thing become that staffers can’t even be bothered to look for synonyms for “evolve” anymore. The DNC might as well print up a form letter — “if you’ve ‘evolved,’ check this box” — and let Democratic holdouts do it that way. In Johnson’s case, the switch is both significant and not: He’s retiring next year so he had zero personally to lose, but his son Brendan’s a contender to replace him and will now have to manage this minor headache. Safe to disagree with dad? It’d be weird for a pol from a younger generation to be less “evolved” than his old man is. Either way, it’s amazing that not even South Dakota politics is immune from this issue anymore.

Only three anti-SSM Dems left in the caucus now: Manchin, Pryor, and Landrieu. Pryor’s been tap-dancing around the subject, assuring liberals that all his gay friends tell him that their orientation isn’t a choice but insisting nonetheless that he’s against SSM. (After a local news outlet reported that he was undecided, he moved quickly to correct them. That’s what a tough reelection campaign in Arkansas will do.) With Johnson now out of the pool, media scrutiny of his position will be even more intense. I’ll bet he flips by the end of summer. As for Landrieu, are we sure she still qualifies as opposed to gay marriage? Watch the short but revealing local-news clip below. Sounds to me like she’s saying yep, she’s “evolved”™ too but that she’s compelled to vote against SSM in order to reflect the view of a majority of Louisianans. Does that principle apply to things like ObamaCare, I wonder, or is it a special rule she’s created purely to avoid a political headache on this issue? And even if it is, why have her views evolved, exactly? If she’s concluded that it’s discriminatory as a matter of equal protection to forbid gays from marrying each other but endorses it anyway in the name of majority rule, i.e. protecting her own career, then arguably she’s in violation of her oath of office. Someone needs to ask a follow-up question, if only for the comic value.