Mostly affects the lower class as Republicans will throw their own kin in front of a bus before they allow the end of tax cuts for the rich.
Republicans generally tend to be richer, more affluent and this can be seen as a defense mechanism more than anything. Needing to find someone to take up the slack they instead make poorer, less fortunate people foot the bill.
Hatred can also be stemmed from the fact that Republicans also tend to spend recklessly on useless stuff, i.e. earmarks. When the shit hits the fan they will often try to cover up their spending by cutting programs that are often beneficial to those other than the rich, i.e. food stamps or unemployment.
Republicans also tend to block or deter the Democrats attempts to fix their mistakes until they can get one of their own candidates in office because they don't want to look bad. This can lead to the Republicans true loyalties/intentions being put into question.
This is the polar opposite of Democraphobia.