Yeah, I'm aware of the Christian Left, they've been around for a while.
They're, for all intents and purposes, playing the same sort of game the Religious Right is playing.
Which is "Look at these half dozen specific verses we found, see how they line up with Party XYZ's platform? That means that voting for Party XYZ is the real Christian thing to do!" (The Christian Right will usually focus on the verses pertaining to verses supporting social conservatism, the Christian Left will usually focus on verses about condemning the rich and giving money to the poor)
--another "fun" symptom of when religion and politics get too intertwined, it starts to become a manipulation tool to get people to vote a certain way by threatening to metaphorically "take away their Christianity card" (in the eyes of their peers) if they vote "the other way"
The only minor distinction is that the proposals from the Christian Left can often be argued from a viewpoint that passes "The Lemon Test" (meaning that it can serve a compelling secular purpose), as to where many of the arguments of the Christian Right are purely religious in nature. In that sense, many of the proposals from the "Christian Left" viewpoint are often more politically durable (in that, they're more likely to pass muster if/when their proposals are challenged at a judicial level).
IE: Even if the reason for a person supporting universal healthcare is their biblical interpretation of helping the poor, a secular case can be made for providing universal healthcare. The same isn't true for things like arguments against same sex marriage, those are almost exclusively religion-based as there's really no argument against things like SSM that's both secular and compelling.