You should not be surprised that Democrats do a great deal of campaigning for Republicans. You can argue that they run half the campaign for them. During the primaries they shread each other, exposing every potentially dammaging facit of thier primary opponents. This leaves the victor, if you can call him/her that, to hobble into the general election as dammaged goods, there for the picking.
When they run their campaigns they should never allow the Republicans to say: “Even ____ (fill in the blank with any of the other primary candidates), said so and so about my opponent!” . What better endorsement do they need? They must never be allowed to cite anything that can be seen as an endorsement of their opinion!!! We must not provide them with this fuel for their campaign.
To the Democrats: RUN ON YOUR OWN MERIT! Simple! We don’t want to hear that we should elect you because the other guy/gal is worse that you! Sell yourself and if your merits are not enough to win, do us all a favor and DROP OUT!