Do a search on Topsy or Google and find where your competition is getting their backlinks for their most popular posts. Their top backlinks are also likely generating the most amount of traffic to their page.
To find the backlinks, use a tool such as Open Site Explorer or SEO Spy Glass. Look for backlinks from other blogs and social bookmarking sites. Then submit your content to the same sources, either via a submission link or by reaching out to the blogger/author as we talk about in the blogger outreach section above.
You can also reverse engineer who shared your competitor’s blog posts. Use a tool like Topsy to do a search on popular posts by your competitors and see who shared them, chances are they will share similar content. Contact them using the outreach strategies below to have them share your content