but that's a bit of a lame argument because that can go for both sides, I
Not really. The (D) for decades has been the "get out the vote" party. It's all about numbers. There are more have-nots than haves. The (D) focus on the have-nots (immigrants, the poor, students). (D) promise freebies to these client constituencies then get them to turn out to vote. The clients vote for (D) because it's the party that delivers the freebies. (D) used to be the party that largely represented blue collar worker votes. When American manufacturing disappeared, they had to shift focus to remain viable.