Honestly I hate to say it, but you friend has done nothing wrong. He has in no way slighted you personally other than disagree with you. If it makes you feel better post something against this politician on your facebook.
I have friends with drastically different opinions/political affiliations than myself, I am able to maintain these friendships because I am able to respect their opinion, and occasionally I actually find they have some valid points and may even change my own opinion. Really it comes down to being able to respect each other's differences, you don't have to agree with them but if you want them to still be friends you need to be able to accept differences, or just drop them as friends
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