You are not abrasive, but you are long winded and speaking to the choir :-)
I have had similar arugments with many people. You can provide history, pertinent facts, ideology, etc.. very little gets through.
Perhaps a change of strategy is in order. I have had some take a few steps back in disbelief:
Do not get into lectures. When in disagreement, keep it short, chuckle, and accuse them of thinking like a democrat. True conservatives, Republicans, absolutely hate that and causes them to go home and think. Also mention that you have a suspicion that a member of congress or senate may be a democrat that has run on a R ticket just to get elected.
It may take time, but you are under the impression that 2016 is a long way off, so there ya go.
Hit me with a PM, we can talk.
"What if the American people learn the truth" - Ron Paul
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