To add a EC Top droppers widget, follow these steps:
Log in to Entrecard.com, in the dash board, click on "More Stats" link, as shown in the image below.
Now "Copy The Link location/shortcut" of the "Top Card Droppers Feed Link", as shown in the picture below.
Now, Log in to Blogger, and go to Layout -> Add a Gadget -> Feed
Then add (paste) the feed link, that you already have copied from the EntreCard account. Save the widget, that's it !
Now enjoy the increase in the number of EC droppers :)