I'm assuming that your content is password protected because you charge for access to it? If that's the case you should consider having this content be ad-free. It takes a whole lot of traffic before advertising provides anyone (you and advertisers) any sort of value. Once you get a sufficiently large (paid) audience, it's likely that you'll find other revenue streams that will provide more value than ads.
Either way, it all depends on the audience makeup, too. If this is a "Myspace" crowd, then you'll need the traffic of MySpace to make it worth your while. If, on the other hand, your audience is Human Resoruces Professionals, then selling direct to companies who want to target that niche could be worth it.
You may want to ask another, more specific question or revise the details on this question. Right now, there's no way to give any more specific advice based on the information provided.