Overall I think it looks pretty good. You've followed a lot of the best practices, such as linking the logo at the top to your website, and keeping the email clear and specific. There are a few things that could be improved on that I saw. In a few places you use just an underline to draw attention to a word. However, your links are also underlined, with no change in the color. This makes it difficult to tell what actually is, or is not a link. Other than that though, I think you're doing a great job!
There are a few things that I would edit/change in your campaign. All of your images, should be linked back to your site or a landing page/blog. I would also make those clickable links into buttons, it just looks less cluttered.
Please let me know if you need anymore help, I've been using Constant Contact for 10+ years and I can really help you out.