In all the post-mortems, we learn this about what it was like inside the Romney campaign:
Romney and his campaign had gone into the evening confident they had a good path to victory, for emotional and intellectual reasons. The huge and enthusiastic crowds in swing state after swing state in recent weeks – not only for Romney but also for Paul Ryan – bolstered what they believed intellectually: that Obama would not get the kind of turnout he had in 2008.
As a result, they believed the public/media polls were skewed – they thought those polls oversampled Democrats and didn't reflect Republican enthusiasm. They based their own internal polls on turnout levels more favorable to Romney. That was a grave miscalculation, as they would see on election night.
Let that sink in for a minute: Team Romney was “unskewing” its internal polls, or maybe they were just using the numbers from the Unskewed Polls guy, who knows, but the point here is that they didn’t like the reality they were getting from their own data collection.
Recap their logic:
1. They got big crowds, therefore,
2. people won't turn out for Obama.
3. If people don't turn out for Obama,
4. then the public polls are skewed.
5. If public polls are skewed,
6. then Romney is winning.
And has a liberal bias.