I wouldn't have thought so but it is always a possibility. They can look at your Facebook and twitter profiles to see who you are connected to. If you have any dodgy things on there that you are telling your friends about then there is always the possibility that any future employer could pick that up and discard your application into the rubbish bin.
A lot of employers do however scan your applications and filter the document through a software program looking for keywords relevant to the position they are trying to fill.
Make sure you have someone check your CV and cover letter before sending to a future employer and give yourself the best chance of being hired.
If you need more information, ask here. https://www.facebook.com/pages/CV-Cover-Letter-Cre...