Adding text widget to sidebar causing distorted site appearance

Someone please help me. It’s important that i’m able to add a text widget to my site, featuredish.com, but i’m noticing a distortion in my site appearance when i do. When i add it to the right sidebar, the bottom of the site appears distorted (the footer and surrounding graphic moves to the left). I’ve tried downloading other text widget plugins other than the default, but they all have the same problems. What can i do to fix this? It only seems to be a problem when i add the text widget, not any other widget.