You can try adding this to your css file:
#productListing {margin-left: 1em; }
Although this will move over the products just a little bit on the rest of your pages too because the Best Sellers page uses the same template and has none of its own id's or classes (as far as I know).
If 1em isn't enough, just keep increasing it a little (1.1, 1.2, etc.) until you can see the line and then check your regular product pages to see if it looks okay too. I'm not the best when it comes to CSS!