Rick's post on Jim Wallis

I am a little surprised at Rick’s response to my post about Jim Wallis. First, Rick chides Wallis for not making it clear that he was speaking as a Protestant. I would have thought that already clear.  Leaving that aside, is it clear that a Bishop has the moral authority to make non-negotiable demands of voters in his diocese on their voting decisions? What if those voters as a matter of conscience regard the demands as unreasonable?   
Second, Rick makes his familiar argument that a Republican will do more to reduce abortions than a Democrat. I think he is probably right. 
But Rick has also said as recently as October 19th, “I've always said here at MOJ that I understand full well that many faithful Catholics will conclude that, all things considered, it's better to vote for the pro-abortion-rights Democrat.  But, I think these faithful Catholics should not dodge the implications of Sen. Obama's election (the same is true, of course, of faithful Catholics who vote for pro-life Republicans whose views on some other serious matters might be flawed.)” I believe each of the principles put forth by Jim Wallis deserve thoughtful consideration.