I think that it never would have been proposed on it's own because this bill, as far as public opinion and political strategy go, is a lose-lose proposition and a vote for it on its own is something that many supporters of the bill (those who have not made it their pet issue) would not have felt comfotable making in the absence of a giant crowd, like 80 or more votes.
Why? this bill barely 'energizes the base' if at all. "Values voters" are more interested in reproductive rights, marriage, stem cell research, regulating nudity and the like. Howerver, their are a bunch of conservative one-issue, poker playing voters now, and many more who would or already do, simply view this type of legislation as one more example of Republicans abandoning traditional conservatism.
So, I think, on its own, this bill is fairly peripheral, but only alienates supporters which, now adays means, it either would never make it to the Senate floor, or it would be tacked onto something.
This is where the House differs from the Senate. The House will bring more marginal bills to the floor and vote on them, the Senate does what it can to avoid doing this.