I think the name-calling really hurt them.
Calling half the voting population bigots of some type just makes that half dig their heels in to give you a bloody nose.
If your main priorities, when running in a political race, does not match the main priorities of the voting masses, it's easier to change your main priorities than to change the main priorities of the voting masses.
For a long time now, the Dems have been trying to change the priorities of the voting masses instead of aligning with them.
They are so used to preaching at their voter base ("This is what a real man is, not what you think it is") that they forgot what the aim of running is - to win.