You also should not underestimate the impact that organic search can have on the success of your website. Our research here at BrightEdge has found that about 51 percent of the traffic on the average site comes from the SERPs. In other words, more people land on your site because of the results pages for particular queries than because of your email, social media, and paid marketing efforts combined.
To do this, I often align the launch of my content with a couple of guest posts on relevant websites to drive a load of relevant traffic to it, as well as some relevant links. This has a knock-on effect toward the organic amplification of the content and means that you at least have something to show for the content (in terms of ROI) if it doesn't do as well as you expect organically.
Remember when you used to rely solely on search engines for traffic? Remember when you worked on SEO and lived and died by your placement in Google? Were you #1? Assured success. Well, okay, maybe not assured. Success only came if the keywords were relevant to your site users, but it was the only real roadmap to generating site traffic and revenue.