I usually see it as calling out the political capture of the two-party system which has rendered the United States an oligarchy with increasingly dysfunctional democratic functions. Quite often it is a call out of the partisanship that reinforces the rigidity of the two party system and preventing any positive or lasting reform. At the very least those are the valid contexts I know of for bringing up any both-sideism of the two American political parties.

But yes, the Republicans do win when there is less voting.