An important new report from Pew Research offers a wealth of information on how Americans view Donald Trump and his presidential transition, but I want to highlight one critical detail in particular: Trump is incredibly unpopular. Take a look at how he stacks up against the last three presidents-elect:

Barack Obama and Bill Clinton both entered office with very positive ratings, and even George Bush, who, like Trump, lost the popular vote and was only handed the White House thanks to the Supreme Court’s extraordinary intervention, was well above water.

But not Trump: His favorability rating stands at a remarkable minus 21 points. And why does this matter? Trump may not be up for re-election for another four years (and god willing, he won’t run again), but Democrats have to remember that when your opponent is unpopular, opposing his agenda is going to be popular! The reverse is also true: If you make any kind of “deal” with Trump, you risk his taint rubbing off on you.

The notion of “mandates” is almost entirely made up, but if anything, Trump has an anti-mandate, given that he won the presidency without winning the popular vote, and given how despised he is. And with those stark facts in hand, Democrats have a mandate to fight him every step of the way.