Political discussion is full of moral dilemmas. I think a debate about ideals and ideas is healthy and that no party (or person) has the "correct" answer, because there simply isn't one. Abortion has so many implications for mothers, the economy and healthcare, religion, sexual crimes, the unborn child, etc. - any policy would have a tradeoff.
If you start attacking a person simply because of their beliefs in politics, I believe it's crossed the line. Society probably doesn't agree with me, since religion is protected and political beliefs aren't, but I personally believe it isn't OK to slander Obama as a person just because he thinks differently.
This is a whole other story - some sports game shouldn't justify anyone from hate-filled speech against a group of race, religion, gender-orientation, etc. I think society would agree with me there. If I'm at an away game and a visiting fan sits down and talks to me about religion and has counterpoints to my beliefs, I'm fine with that. I've had that happen from a classy Christian dude at an away game, who was quite adamant that he didn't believe in all the stuff Mormons believed in (or what he thought we believed in), but wasn't going to make jello shots of sacrament cups or tell my cousin that she is "ugly, even for a Mormon...must have been knocked up too many times".
Therefore, while I don't agree with either, I'm much more likely to push against one over the other. I also think political discussions take that path because people have to take what they dish out, and during an election year there is plenty of mudslinging from both sides (and both sides go "too far").
Hope that makes sense.