Become a "fan" of his key opponents. Then if you can subtly introduce Paul viewpoints/commentary (along with not having a RP 2012 avatar) you can start some discussions on the opponent fan pages.
Even if you don't do this, posting links to Ron Paul videos or statements on your own facebook page tends to generate some conversation - I usually throw in some meat for fans of other politicians to get them engaged. The is "Paul more progressive than Obama" article generated a great deal of discussion.
Also, it makes sense to subscribe to the mailing lists of other candidates (put in one of your throw-away email addresses ) or their RSS feeds. Then you can at least stay in the loop (for instance when they post a new video and want positive feedback).
Also, it makes sense to sign up for one of his opponents forums NOW! All the Truthers in here want to discredit me and anything thing I say (even though I have supported and funded Ron for ages) because of my account age, so it might be good to go and find the Romney, Pawlenty, Huckabee etc forums and get an account, if only to say "hi" for now. Then if one of them seems like they are pulling ahead, that can be one to focus on with the subtle Ron Paul messaging, without the "you signed up 2 days, thus are incorrect" logical fallacy.
I guess the overall point with this is - as you say - to strategically put out the message of Ron where his message would be very unwelcome (just because it is Ron Paul); being abrasive about it (Ron Paul! Ron Paul! 911 Truth!) often has just gets his viewpoints rejected without consideration.
Oh, and please do NOT do any of this, as Joη says. :P
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