In all my adult life attending Mass I have NEVER had a priest tell me to vote for a specific candidate or even a specific party. Yes, the Priests will discuss the Catholic teaching on social issues, but I've never been told that I should vote one way or the other.
As far as the Communion thing, why would someone who has rejected Catholic teaching want to receive Communion anyway? I've never really understood that. If I'm going to receive, I need to be in a state of grace and aligned with Church teaching. If I had in any way directly enabled someone so that they could commit a serious sin, I would not be able to receive communion worthily. I would have to go to confession and resolve not to commit that serious sin again. If I go right back out and keep doing it, then my contrition was false. If I disagreed so fundamentally with the teaching of the Church that I could not consistently obey it, and enabled others to disobey it as well, then I wouldn't be Catholic anymore. Family members and friends have left for reasons of conscience and I completely respect that.
If a Catholic politician has made it easier for someone else to commit a sin, then he/she would be in the same position. I don't believe in abortion, I've never had one and I've never directly assisted in anyone else having one either. I also haven't directly assisted in sending anyone off to Iraq. Sure, my taxes are funding it, but I didn't cast a vote to go to war.
It seems that some Catholic politicians like being Catholic when they're getting contributions at the Knights of Columbus dinner, but they're pretty ready to renounce Church teaching when they head over to the NOW meeting.