Split your list of long tail keywords into related groups. Write a blog post about each group and include all the keywords in that group in the blog post. Make the highest traffic keyword in each group the "target keyword" for each post and then fill the post out with the other keywords in that group. Create external backlinks to each blog post, and use the keywords in each group as the anchor text. Voila, you will start getting long tail traffic for keywords you weren't hitting before.