The reason Democrats don't lie as much as Republicans is because they don't have to. In general, they want a more pluralistic America, a better regulated economy, a better safety net, and a more progressive taxation system.
They want what they want, and the rest is just agreeing on the details and how to sell it/explain it/argue for it. No lies needed. Ever.
Republicans, on the other hand, want a white ethno-state with a fascist government, run by an oligarchy, like they have in Russia and other "banana republics."
You can't sell that crap to decent humans, so they have to lie, lie, lie.