I wouldn't rule it out, but it isn't necessary.
Voter fraud is just too easy; if they want Obama to stay, he will stay. We have almost no ability to know the real and legal vote count. We have almost no ability to pick our own candidates. They gave us Romney as an alternative to Obama. They put a president in office who can not legally hold that office. And yet none of us can do, or will do anything about it.
I think that the Olympics in London could be their next shock and awe hoax. I hope not.