A: 

make sure you are using the correct doctype

John Boker
+1  A: 

The input is inheriting the margins from the surrounding div and the ol. If you surround it with another tag like a span or a div, it should solve your problem.

Edit: You can find more information and workarounds at http://www.positioniseverything.net/explorer/inherited_margin.html

Matthew Crumley
I'll give that a try, but I already tried this: .FormGroup > *{ margin: 0 0 0 0; float:left; background-color: Yellow;} to override the margin from the parent <div> and it didn't work. I'll try the extra span or div, but hopefully there is a prettier way.
CMPalmer
The link looks great - I'll try it tomorrow and post my results. Looks like the right answer just from reading the article, though!
CMPalmer