Lets be serious here...THE POPULACE DOES NOT GIVE A RATS ASS ABOUT SOURCE CODE!!!!!!!
 
Now that that's said and done, I believe that the voting system can be either closed or open source, but what really matters is when the law comes in and asks for source code a company should exonerate itself by giving the source code. On the flip side, if its closed source, they should also have the right to protect their intellectual property. It's a tricky situation, but with a little social responsibility closed source software might be the way to go.
 
Always remember, its closed source software that feeds your kids.