Republicans talking about skewed polls were the most egregious example, but nonpartisan media was generally calling the election "razor tight", "a tossup" and similar things, too. In their case, the reason seems to be an ignorance of how statistics works. E.g. seeing polls with Obama up by 2% and a margin of error of 3, they would label it "a statistical tie", even though a) even with a single such poll, it implies a much higher chance of Obama winning, and b) with many polls giving numbers in that range, the chances of Romney being actually ahead drop to near-zero, barring systematic error.