In 2008 and 2012, the political media was myopically focused on the twists and turns of the horse race and called it 50-50 dead even. Nate Silver's 538 modeled the election as basically stable with only small polling shifts, and the only change in the last month was a steady decline in the remaining time that McCain (or Romney) had to significantly shift the polls.
In 2016, the political media treated the election as if Hillary had a lock on it, and entreated us not to get swept up in the daily swings in the polls. Meanwhile, Nate Silver's model swung wildly with the polls, and Nate went on the media to emphasize the uncertainty of the election. Both candidates were disliked, and a large portion of the electorate was undecided right up until the last week of the election.
I remember the following exchange in one interview:
Interviewer: If you say that Donald Trump has a 33% chance to win, what's the chance that he actually wins? Nate Silver: One in three. I'm predicting a one in three chance that Donald Trump wins in November.
As for the authoritativeness of their presentation, FiveThirtyEight has a really beautiful forecast that presents their 2018 prediction as a probability distribution:
https://projects.fivethirtyeight.com/2018-midterm-election-f...