I am not a Trump apologist, though I did vote for him.  Let me make some observations to your comment:

It is true that Trump did not win the majority vote.  That is irrelevant.  In this country the electoral college elects the president. The college prevents certain areas of the country (CA and NY) from dominating presidential elections and allows the smaller population states to have a greater influence.  Trump won the electoral college and that is all that matters.  

Why this should matter to liberals is that it shows them that high population states like CA and NY aren't the only ones that matter.  They have to find ways to reach out to the average voter and common man--rather than rich, white and elite suburbanites at their rich, white and elite country clubs, drinking their rich, elite 75 dollar a glass scotch, with their pinky in the air congratulating themselves on caring about people. 

In short--I think the arrogance and snobbery of the left contributed to their loss.