More likely the poll began to trend in Romney's favor, so they terminated the polling.
The polling sample is small and is probably D+ oversampled. Romney is behind by -1 but that’s not what the internals show.
The internals paint a completely different picture. And when you look at them, you can see that O has no chance. He’s not breaking 50% even in a CBS/NYT poll, which is one of the very worst polls out there.
Its all over.