Polls show that more and more Americans are okay with gay marriage, but that's not being reflected in recent votes on the issue. But there have been some pretty big--and pretty sudden--shifts in opinions since President Obama came out in support of marriage rights. There's something to be said for the power of the presidential bully pulpit.
Hopefully, any upcoming votes will reflect actual American attitudes... even though it's appalling that the rights of some people are up for a vote. Black civil rights would never have been supported in votes in the south back in the 60s... or probably even today in some teabagger-ridden areas.