I could have seen 20+ stand against it on the grounds of the TG component if they felt they could defeat the bill. However, once a few Republicans peel away and defeat is assured, the GOP will usually read the writing on the wall and get the heck out of the way, especially since appearing "pro-bully" (whether fair or not) does not look good on TV.
I like the result, but the context of some of the those votes is worth considering.