OKCupid recently released some data on its users, and reported that women who message men first are having more success on the site. Online dating is never easy, so a little insider advice can't hurt. They specifically looked at the behavior of sending the first message to a potential date. It turns out that people often originate a conversation with someone they feel is more attractive than they are:

When we looked specifically at sending the first message, we found one striking habit: everyone’s a reacher, meaning people tend to reach out to someone more attractive than they are. To put a number on it, men are reaching out to women 17 percentile points more attractive, and women contact men who are 10 percentile points more attractive. This means that if a woman does nothing, her inbox will be filled with less attractive men.

Sources: The New York Times | OKCupid