David McPherson at First Things is posing the question and offering up a possible answer, particularly as it pertains to The American Solidarity Party:
While the ASP is shaped by a Christian worldview, it welcomes all people who find its vision for society compelling, even if they do not share in the same faith. And despite what John Rawls and other liberal political philosophers say, there is in fact no worldview-neutral standpoint; we cannot and should not leave our comprehensive religious, philosophical, and moral understandings at the door when we engage in political argument.
In Habits of the Heart, Robert Bellah and his co-authors have shown the importance of the biblical tradition as a “second language” in American public life. It is hard to imagine how barren our public life would be without this tradition. (Think of what the speeches of Martin Luther King, Jr. would have been like without his use of biblical language.) In the West, as Gaita notes, our languages of love and solidarity have been especially shaped by the biblical tradition and by certain saintly exemplars. Rather than ignore this cultural inheritance, we should gratefully acknowledge it, embrace it, and seek to strengthen it.
Another question for the ASP is this: Why should someone vote for a party that won’t win, especially in this election, when so much is at stake in terms of foreign relations, the economy, Supreme Court appointments, democratic rule of law, and so on? Isn’t it better to vote for the major-party candidate who seems the least bad?
Many people of goodwill are going to make this decision. But for those who cannot in good conscience vote for either Clinton or Trump—say, because of the candidates’ stances against the sanctity of human life—voting for the ASP may be seen as a protest vote against a system that presents us with such poor choices. But it is not merely a protest vote, because if we are to work fully toward the kind of politics we need, we must first break from the political status quo. The ASP should thus be understood as seeking primarily to build up a cultural movement, which ideally will come to have political influence.
So what are the long-term prospects for this politics of solidarity? In Fyodor Dostoevsky’s The Brothers Karamazov, Father Zosima, as a young man, asked a very similar question, to which his friend responded:[W]e must keep the banner flying. Sometimes even if he has to do it alone, and his conduct seems to be crazy, a man must set an example, and so draw men’s souls out of their solitude, and spur them to some act of brotherly love even if he seems crazy, so that the great idea may not die.
The American Solidarity Party, as I see it, is an attempt to “keep the banner flying.”
Thoughtful piece, read the whole thing.