This chart is from an NBC News / Wall Street Journal Poll -- done between December 12th and 15th of a random national sample of 1,000 adults, and has a margin of error of 3.1 points.
It shows that a majority of Americans (54%) are either uncertain (25%) or pessimistic (29%) about Donald Trump being elected president. This is the first time since this poll has been taken that the incoming president has more people worried about him than optimistic (22%) or satisfied (23%).
This is significantly worse than either of the last two presidents when they were about to be sworn in. While Trump's numbers are 45%/54%, Obama's were 66%/33% and Bush II's were 59%/40%.
It's obvious that Trump has no mandate. He still has a lot of work to do to convince a majority of Americans he might be a good president.