The issue of economic disparity seems impossible to address effectively within the current US two-party system and accompanying campaign finance mechanisms. If the economic inequalities are an issue of injustice, then it seems that they must be serving justice, as long as they do no harm.
Effectiveness is another question: would it be the passage of the “Robin Hood Tax” (and to what extent would it be watered down), the starting of a movement or the passage of certain legislative reforms that would mark it as successful? I would argue that they have already been effective at focusing attention on the issue. How far will they go? That would seem to depend on their creativity and leadership.
Inviting them in (as with the sanctuary movement) seems like a great way for the church to be supportive.
Links,