At least in the smoking example, it's not necessarily denial; addiction is a powerful thing. People are used to their way of life, and Trump represents the status quo (which so do Democrats, but whatever) People are too afraid of the change, or afraid they'll be unable to handle the change, so they may hold their nose and vote for him. Denial is certainly a possibility, and in the case of Trump it may be the more likely option. But fear and routine certainly influence people too without necessarily driving them into deep denial.