Hi, unfortunately because the Coming Soon Plugin is rendered completely outside of the normal WordPress rendering cycle, the plugin doesn’t support shortcodes. However, it does support HTML for all fields.
You could do one of two things:
1) Find a Constant Contact HTML form that allows you to submit directly to them and include that in the description field while turning off standard Coming Soon Page email collection.
or
2) Collect emails using the Coming Soon subscriber capability then export the list as CSV (comma separated values) and import into Constant Contact. The process is explained here: http://easypiewp.com/creating-mailing-list-coming-soon-page-subscribers/
Bob
I did grab the html off of a page after inserting the shortcode.
Thanks for the quick reply!