Google adsense ads are content driven. I don't know the technical jargon, but Google has a way of analyzing the content of a website or blog and attempts to target the folks most likely to be visiting said blog or website.
Yesterday, while posting on my D'offus of the Big-Doofus blog, I noticed that the ads across the top of page were all directed towards folks applying for welfare.
The little Google crawlers or spiders (or whatever they're called), picked up on "Obama" and "Hillary Clinton" and "Joe Biden" in the blog content and decided that most of the visitors to that blog must be interested in signing up for government assistance.
I guess you can't really expect Google crawlers or spiders (or whatever they're called), to understand parody. As Al pointed out in his comment on Washington sends $1 Food Stamp Checks ;
"Kind of scary when what starts out as a spoof actually becomes reality, isn't it?"