Contacting voters inobtrusively

All you readers are pretty political. At least, some of you are. I have a question:

I'd like to try to convince people to vote for Barack Obama. But I don't want to go door-to-door, and I don't want to call people. It's a matter of principle: I HATE HATE HATE HATE HATE telemarketers, and like it or not, calling people for Obama is just as annoying as calling people to sell them a thing. Same with going door-to-door; it's a little nicer because you get some human contact, but it's still bothersome. (almost. maybe 75% as bothersome. still more bothersome than I want to be.)

What should I do, dear readers? I'd like to email voters, but that's as insincere as it gets: it'd just be a form letter. Plus, I don't have an email list. Another option is standing out on the street and talking to passersby if they look interested in talking. Actually, I'd like that: stand out with a sign that says "Talk to me about voting for Obama" or even just "talk politics with me!" and people can talk to me if they want. Basically, I want an opt-in, not an opt-out, method of convincing people. It seems more civilized that way.