Erm, Clinton seems to have the popular vote. So I'm exactly sure what mandate you're referring to, but this is a forum about US politics.
Control of the Presidency, the Senate, and the House isn't enough of a mandate for you.....?
Did Obama have a Mandate in 2008? He won the Presidency, the House, and a philibuster proof senate.
Mandate is a pretty stupid word all told. But I would definitely question the word Mandate here. It's looking like Trump lost the popular vote. So he has control. The GOP has control. But I'd be careful about tossing around the word Mandate. Winning through the Electoral college isn't a mandate. Winning gerrymandered House Seats isn't much of a mandate either. And the GOP didn't get a supermajority in the Senate. They'll maybe finish at 53 total Senators. So it's not philibuster proof.
Again, I don't see a lot of folks that would claim now Obama had a mandate in 2008, and his win was arguably larger.
But I will concede this: Trump has a responsibility to his voters. Obama did a lot with executive orders after Congress became deadlocked. He can undo some of the most unpopular parts of Obama's legacy on day one if he so chooses. And if he doesn't, his voters should hold him accountable.