"In the last decade one of the changes we have seen in the online world is the advent of commercial cyber crime services. Here is an example of one, a company that has tiered rates for the amount of spam email it will dump on a target at your request.
http://boingboing.net/2012/07/19/commercial-spamflooding-used-b.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+boingboing%2FiBag+%28Boing+Boing%29
This could easily overload the servers or distract the staffs of an election service on election day if it accepted ballots by email. The staff could not just systematically dump all 100,000 spam emails because scattered among them would be real ballots, so they would need to spend time to diagnose a means of reliably distinguishing ballots from spam, and then write, debug, and test a script to filter the ballots from the email stream. Depending on the details, this could take hours of careful work. And look at the prices! Only $70 for 100,000 spam emails from many different IP addresses!"