Earlier this year Buzzfeed noted the "strange devolution of Obama campaign emails," if you compare 2012 to 2008. In 2008 the subject-lines often referred to data and campaign strategy; in 2012 they're more often "hectoring, manipulative and full of angst."
Julie Beck at the Hairpin obviously saw a similar trend when she rounded up "Subject Lines of Obama Campaign Emails That Sound Like a Stalker Wrote Them":
"Something I'd like to ask you"
"What's stopping you, right now?"
"Sometime soon, can we meet for dinner?"
"You must be at least a little curious"
"I'm not shy"