You're probably right, If Mitt wins the popular vote but Obama still wins, my guess is a 4 year filibuster from the House is on its way.
There isn't any such a thing as the filibuster in the House; the Senate, however, will certainly be no better now than it has been. Republicans have been trying for the last 4 years to prevent an Obama re-election (Mitch McConnell number one stated priority), and if he wins re-election, than it'll be about trying to prevent Democrats from winning in 2016.
Though, if Obama doesn't win the Popular vote now, there'll be a valid question of how much that is due to Sandy. Obama will still win the blue northeast, but voter turnout could easily be lower, meaning he won't get as many votes.
Although as the record shows, it doesn't mean he won't get anything done. Which, by the way, I think people really underplay just how much Obama has managed to get done with what is arguably the most gridlocked legislature in American history.
Only so much can be done through executive orders and use of department oversight. This just highlights the lunacy of politics in general. I'm amazed more people haven't given up on it yet.
Maybe that's because, at the end of the day, most people realize that government is necessary and for the better good.