No offense but calling democrats "the dims" is stupid. If you cannot refrain from calling a political group you disagree with a insulting term, do you believe people are going to think "This man/woman sounds like he/she has a good head on his/her shoulders. I should listen to him/her." or "This man/woman sounds like he/she can't be respectful towards people he/she doesn't agree with"?
Anyway, the endgame of both political parties is "to strengthen the voter base for their party" as you put it. A recent example is Trump saying that immigrants will overrun the US. If this is so unacceptable to the american people, they may vote for another politician(s) who does not hold favorable beliefs towards them. At the end of the day, the people vote for those whose beliefs most concur with theirs or not at all.